Add initial support for packages and imports

Makefile

@@ -1,14 +1,14 @@
 
-TREEGEN_FILES = spec/ast.txt lib/bin/bolt-treegen.js lib/treegen/parser.js lib/treegen/index.js lib/treegen/util.js src/treegen/ast-template.js
+TREEGEN_FILES = src/ast-spec.txt lib/bin/bolt-treegen.js lib/treegen/parser.js lib/treegen/index.js lib/treegen/util.js src/treegen/ast-template.js
 
 all: lib/ast.js
-	bolt bundle test.bolt
+	bolt bundle stdlib
 
 lib/ast.js: $(TREEGEN_FILES)
 	@echo "Generating AST definitions ..."
 	@mkdir -p lib/
 	@chmod +x lib/bin/*.js
-	@bolt-treegen --js-file=lib/ast.js --dts-file src/ast.d.ts spec/ast.txt
+	@bolt-treegen --js-file=lib/ast.js --dts-file src/ast.d.ts src/ast-spec.txt
 
 lib/treegen/parser.js: src/treegen/parser.pegjs
 	@echo "Generating parser ..."

package-lock.json

@@ -38,6 +38,11 @@
         "@types/node": "*"
       }
     },
+    "@types/js-yaml": {
+      "version": "3.12.4",
+      "resolved": "https://registry.npmjs.org/@types/js-yaml/-/js-yaml-3.12.4.tgz",
+      "integrity": "sha512-fYMgzN+9e28R81weVN49inn/u798ruU91En1ZnGvSZzCRc5jXx9B2EDhlRaWmcO1RIxFHL8AajRXzxDuJu93+A=="
+    },
     "@types/microtime": {
       "version": "2.1.0",
       "resolved": "https://registry.npmjs.org/@types/microtime/-/microtime-2.1.0.tgz",
@@ -64,6 +69,14 @@
       "resolved": "https://registry.npmjs.org/@types/node/-/node-14.0.5.tgz",
       "integrity": "sha512-90hiq6/VqtQgX8Sp0EzeIsv3r+ellbGj4URKj5j30tLlZvRUpnAe9YbYnjl3pJM93GyXU0tghHhvXHq+5rnCKA=="
     },
+    "@types/semver": {
+      "version": "7.2.0",
+      "resolved": "https://registry.npmjs.org/@types/semver/-/semver-7.2.0.tgz",
+      "integrity": "sha512-TbB0A8ACUWZt3Y6bQPstW9QNbhNeebdgLX4T/ZfkrswAfUzRiXrgd9seol+X379Wa589Pu4UEx9Uok0D4RjRCQ==",
+      "requires": {
+        "@types/node": "*"
+      }
+    },
     "@types/yargs": {
       "version": "15.0.5",
       "resolved": "https://registry.npmjs.org/@types/yargs/-/yargs-15.0.5.tgz",
@@ -111,7 +124,6 @@
       "version": "1.0.10",
       "resolved": "https://registry.npmjs.org/argparse/-/argparse-1.0.10.tgz",
       "integrity": "sha512-o5Roy6tNG4SL/FOkCAN6RzjiakZS25RLYFrcMttJqbdd8BWrnA+fGz57iN5Pb06pvBGvl5gQ0B48dJlslXvoTg==",
-      "dev": true,
       "requires": {
         "sprintf-js": "~1.0.2"
       }
@@ -353,8 +365,7 @@
     "esprima": {
       "version": "4.0.1",
       "resolved": "https://registry.npmjs.org/esprima/-/esprima-4.0.1.tgz",
-      "integrity": "sha512-eGuFFw7Upda+g4p+QHvnW0RyTX/SVeJBDM/gCtMARO0cLuT2HcEKnTPvhjV6aGeqrCB/sbNop0Kszm0jsaWU4A==",
+      "integrity": "sha512-eGuFFw7Upda+g4p+QHvnW0RyTX/SVeJBDM/gCtMARO0cLuT2HcEKnTPvhjV6aGeqrCB/sbNop0Kszm0jsaWU4A=="
-      "dev": true
     },
     "fill-range": {
       "version": "7.0.1",
@@ -576,10 +587,9 @@
       "dev": true
     },
     "js-yaml": {
-      "version": "3.13.1",
+      "version": "3.14.0",
-      "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-3.13.1.tgz",
+      "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-3.14.0.tgz",
-      "integrity": "sha512-YfbcO7jXDdyj0DGxYVSlSeQNHbD7XPWvrVWeVUujrQEoZzWJIRrCPoyk6kL6IAjAG2IolMK4T0hNUe0HOUs5Jw==",
+      "integrity": "sha512-/4IbIeHcD9VMHFqDR/gQ7EdZdLimOvW2DdcxFjdyyZ9NsbS+ccrXqVWDtab/lRl5AlUqmpBx8EhPaWR+OtY17A==",
-      "dev": true,
       "requires": {
         "argparse": "^1.0.7",
         "esprima": "^4.0.0"
@@ -741,6 +751,16 @@
             "path-is-absolute": "^1.0.0"
           }
         },
+        "js-yaml": {
+          "version": "3.13.1",
+          "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-3.13.1.tgz",
+          "integrity": "sha512-YfbcO7jXDdyj0DGxYVSlSeQNHbD7XPWvrVWeVUujrQEoZzWJIRrCPoyk6kL6IAjAG2IolMK4T0hNUe0HOUs5Jw==",
+          "dev": true,
+          "requires": {
+            "argparse": "^1.0.7",
+            "esprima": "^4.0.0"
+          }
+        },
         "string-width": {
           "version": "3.1.0",
           "resolved": "https://registry.npmjs.org/string-width/-/string-width-3.1.0.tgz",
@@ -825,6 +845,14 @@
       "requires": {
         "object.getownpropertydescriptors": "^2.0.3",
         "semver": "^5.7.0"
+      },
+      "dependencies": {
+        "semver": {
+          "version": "5.7.1",
+          "resolved": "https://registry.npmjs.org/semver/-/semver-5.7.1.tgz",
+          "integrity": "sha512-sauaDf/PZdVgrLTNYHRtpXa1iRiKcaebiKQ1BJdpQlWH2lCvexQdX55snPFyK7QzpudqbCI0qXFfOasHdyNDGQ==",
+          "dev": true
+        }
       }
     },
     "node-gyp-build": {
@@ -955,10 +983,9 @@
       "integrity": "sha512-NKN5kMDylKuldxYLSUfrbo5Tuzh4hd+2E8NPPX02mZtn1VuREQToYe/ZdlJy+J3uCpfaiGF05e7B8W0iXbQHmg=="
     },
     "semver": {
-      "version": "5.7.1",
+      "version": "7.3.2",
-      "resolved": "https://registry.npmjs.org/semver/-/semver-5.7.1.tgz",
+      "resolved": "https://registry.npmjs.org/semver/-/semver-7.3.2.tgz",
-      "integrity": "sha512-sauaDf/PZdVgrLTNYHRtpXa1iRiKcaebiKQ1BJdpQlWH2lCvexQdX55snPFyK7QzpudqbCI0qXFfOasHdyNDGQ==",
+      "integrity": "sha512-OrOb32TeeambH6UrhtShmF7CRDqhL6/5XpPNp2DuRH6+9QLw/orhp72j87v8Qa1ScDkvrrBNpZcDejAirJmfXQ=="
-      "dev": true
     },
     "set-blocking": {
       "version": "2.0.0",
@@ -982,8 +1009,7 @@
     "sprintf-js": {
       "version": "1.0.3",
       "resolved": "https://registry.npmjs.org/sprintf-js/-/sprintf-js-1.0.3.tgz",
-      "integrity": "sha1-BOaSb2YolTVPPdAVIDYzuFcpfiw=",
+      "integrity": "sha1-BOaSb2YolTVPPdAVIDYzuFcpfiw="
-      "dev": true
     },
     "string-width": {
       "version": "4.2.0",

package.json

@@ -16,18 +16,22 @@
   "dependencies": {
     "@types/fs-extra": "^9.0.1",
     "@types/glob": "^7.1.1",
+    "@types/js-yaml": "^3.12.4",
     "@types/microtime": "^2.1.0",
     "@types/minimist": "^1.2.0",
     "@types/node": "^14.0.5",
+    "@types/semver": "^7.2.0",
     "@types/yargs": "^15.0.5",
     "chalk": "^4.0.0",
     "fs-extra": "^9.0.0",
     "glob": "^7.1.6",
+    "js-yaml": "^3.14.0",
     "microtime": "^3.0.0",
     "minimist": "^1.2.5",
     "moment": "^2.26.0",
     "pegjs": "^0.11.0-master.b7b87ea",
     "reflect-metadata": "^0.1.13",
+    "semver": "^7.3.2",
     "source-map-support": "^0.5.19",
     "yargs": "^15.3.1"
   },

src/ast-spec.txt

@@ -67,6 +67,7 @@ node BoltLoopKeyword    > BoltToken, BoltKeyword;
 node BoltYieldKeyword   > BoltToken, BoltKeyword;
 node BoltMatchKeyword   > BoltToken, BoltKeyword;
 node BoltImportKeyword  > BoltToken, BoltKeyword;
+node BoltExportKeyword  > BoltToken, BoltKeyword;
 node BoltPubKeyword     > BoltToken, BoltKeyword;
 node BoltModKeyword     > BoltToken, BoltKeyword;
 node BoltMutKeyword     > BoltToken, BoltKeyword;
@@ -86,6 +87,7 @@ node BoltBracketed > BoltPunctuated;
 
 node BoltSourceFile > SourceFile {
   elements: Vec<BoltSourceElement>,
+  package: Package,
 }
 
 node BoltQualName {
@@ -237,15 +239,13 @@ node BoltDeclaration > BoltSourceElement;
 
 node BoltTypeDeclaration > BoltSourceElement;
 
-enum BoltDeclarationModifiers {
+enum BoltModifiers {
-  Mutable   = 0x1,
+  IsMutable   = 0x1,
-  Public    = 0x2,
+  IsPublic    = 0x2,
-  IsType    = 0x4,
-  IsForeign = 0x8,
 }
 
-node BoltModule > BoltDeclaration {
+node BoltModule > BoltSourceElement {
-  modifiers: BoltDeclarationModifiers,
+  modifiers: BoltModifiers,
   name: BoltQualName,
   elements: Vec<BoltSourceElement>,
 }
@@ -253,7 +253,7 @@ node BoltModule > BoltDeclaration {
 node BoltFunctionBodyElement;
 
 node BoltFunctionDeclaration > BoltFunctionBodyElement, BoltDeclaration {
-  modifiers: BoltDeclarationModifiers,
+  modifiers: BoltModifiers,
   target: String,
   name: BoltSymbol,
   params: Vec<BoltParameter>,
@@ -263,7 +263,7 @@ node BoltFunctionDeclaration > BoltFunctionBodyElement, BoltDeclaration {
 }
 
 node BoltVariableDeclaration > BoltFunctionBodyElement, BoltDeclaration {
-  modifiers: BoltDeclarationModifiers,
+  modifiers: BoltModifiers,
   bindings: BoltPattern,
   type: Option<BoltTypeExpression>,
   value: Option<BoltExpression>,
@@ -275,20 +275,32 @@ node BoltPlainImportSymbol > BoltImportSymbol {
   name: BoltQualName,
 }
 
-node BoltImportDeclaration > BoltDeclaration {
+node BoltImportDirective > BoltSourceElement {
+  modifiers: BoltModifiers,
   file: String,
   symbols: Vec<BoltImportSymbol>,
 }
 
+node BoltExportSymbol;
+
+node BoltPlainExportSymbol {
+  name: BoltQualName,
+}
+
+node BoltExportDirective > BoltSourceElement {
+  file: String,
+  symbols: Option<Vec<BoltExportSymbol>>,
+}
+
 node BoltTraitDeclaration > BoltDeclaration, BoltTypeDeclaration {
-  modifiers: BoltDeclarationModifiers,
+  modifiers: BoltModifiers,
   name: BoltIdentifier,
   typeParams: Option<Vec<BoltTypeParameter>>,
   elements: Vec<BoltDeclaration>,
 }
 
 node BoltImplDeclaration > BoltDeclaration {
-  modifiers: BoltDeclarationModifiers,
+  modifiers: BoltModifiers,
   name: BoltIdentifier,
   trait: BoltTypeExpression,
   typeParams: Option<Vec<BoltTypeParameter>>,
@@ -296,7 +308,7 @@ node BoltImplDeclaration > BoltDeclaration {
 }
 
 node BoltTypeAliasDeclaration > BoltDeclaration, BoltTypeDeclaration {
-  modifiers: BoltDeclarationModifiers,
+  modifiers: BoltModifiers,
   name: BoltIdentifier,
   typeParams: Option<Vec<BoltTypeParameter>>,
   typeExpr: BoltTypeExpression,
@@ -310,7 +322,7 @@ node BoltRecordField > BoltRecordMember {
 }
 
 node BoltRecordDeclaration > BoltDeclaration, BoltTypeDeclaration {
-  modifiers: BoltDeclarationModifiers,
+  modifiers: BoltModifiers,
   name: BoltIdentifier,
   typeParms: Option<Vec<BoltTypeParameter>>,
   members: Option<Vec<BoltRecordMember>>,

src/ast.d.ts

@@ -1,4 +1,9 @@
 
+import { Package } from "./common"
+
+export function isSyntax(value: any): value is Syntax;
+
+
 export const enum SyntaxKind {
   EndOfFile = 2,
   FunctionBody = 6,
@@ -32,121 +37,125 @@ export const enum SyntaxKind {
   BoltYieldKeyword = 38,
   BoltMatchKeyword = 39,
   BoltImportKeyword = 40,
-  BoltPubKeyword = 41,
+  BoltExportKeyword = 41,
-  BoltModKeyword = 42,
+  BoltPubKeyword = 42,
-  BoltMutKeyword = 43,
+  BoltModKeyword = 43,
-  BoltEnumKeyword = 44,
+  BoltMutKeyword = 44,
-  BoltStructKeyword = 45,
+  BoltEnumKeyword = 45,
-  BoltTypeKeyword = 46,
+  BoltStructKeyword = 46,
-  BoltTraitKeyword = 47,
+  BoltTypeKeyword = 47,
-  BoltImplKeyword = 48,
+  BoltTraitKeyword = 48,
-  BoltParenthesized = 50,
+  BoltImplKeyword = 49,
-  BoltBraced = 51,
+  BoltParenthesized = 51,
-  BoltBracketed = 52,
+  BoltBraced = 52,
-  BoltSourceFile = 53,
+  BoltBracketed = 53,
-  BoltQualName = 54,
+  BoltSourceFile = 54,
-  BoltReferenceTypeExpression = 56,
+  BoltQualName = 55,
-  BoltFunctionTypeExpression = 57,
+  BoltReferenceTypeExpression = 57,
-  BoltTypeParameter = 58,
+  BoltFunctionTypeExpression = 58,
-  BoltBindPattern = 60,
+  BoltTypeParameter = 59,
-  BoltTypePattern = 61,
+  BoltBindPattern = 61,
-  BoltExpressionPattern = 62,
+  BoltTypePattern = 62,
-  BoltTuplePatternElement = 63,
+  BoltExpressionPattern = 63,
-  BoltTuplePattern = 64,
+  BoltTuplePatternElement = 64,
-  BoltRecordFieldPattern = 65,
+  BoltTuplePattern = 65,
-  BoltRecordPattern = 66,
+  BoltRecordFieldPattern = 66,
-  BoltQuoteExpression = 68,
+  BoltRecordPattern = 67,
-  BoltReferenceExpression = 69,
+  BoltQuoteExpression = 69,
-  BoltMemberExpression = 70,
+  BoltReferenceExpression = 70,
-  BoltFunctionExpression = 71,
+  BoltMemberExpression = 71,
-  BoltCallExpression = 72,
+  BoltFunctionExpression = 72,
-  BoltYieldExpression = 73,
+  BoltCallExpression = 73,
-  BoltMatchArm = 74,
+  BoltYieldExpression = 74,
-  BoltMatchExpression = 75,
+  BoltMatchArm = 75,
-  BoltCase = 76,
+  BoltMatchExpression = 76,
-  BoltCaseExpression = 77,
+  BoltCase = 77,
-  BoltBlockExpression = 78,
+  BoltCaseExpression = 78,
-  BoltConstantExpression = 79,
+  BoltBlockExpression = 79,
-  BoltReturnStatement = 81,
+  BoltConstantExpression = 80,
-  BoltConditionalCase = 82,
+  BoltReturnStatement = 82,
-  BoltConditionalStatement = 83,
+  BoltConditionalCase = 83,
-  BoltResumeStatement = 84,
+  BoltConditionalStatement = 84,
-  BoltExpressionStatement = 85,
+  BoltResumeStatement = 85,
-  BoltParameter = 86,
+  BoltExpressionStatement = 86,
-  BoltModule = 90,
+  BoltParameter = 87,
-  BoltFunctionDeclaration = 92,
+  BoltModule = 91,
-  BoltVariableDeclaration = 93,
+  BoltFunctionDeclaration = 93,
-  BoltPlainImportSymbol = 95,
+  BoltVariableDeclaration = 94,
-  BoltImportDeclaration = 96,
+  BoltPlainImportSymbol = 96,
-  BoltTraitDeclaration = 97,
+  BoltImportDirective = 97,
-  BoltImplDeclaration = 98,
+  BoltExportSymbol = 98,
-  BoltTypeAliasDeclaration = 99,
+  BoltPlainExportSymbol = 99,
-  BoltRecordField = 101,
+  BoltExportDirective = 100,
-  BoltRecordDeclaration = 102,
+  BoltTraitDeclaration = 101,
-  BoltMacroCall = 104,
+  BoltImplDeclaration = 102,
-  JSOperator = 107,
+  BoltTypeAliasDeclaration = 103,
-  JSIdentifier = 108,
+  BoltRecordField = 105,
-  JSString = 109,
+  BoltRecordDeclaration = 106,
-  JSInteger = 110,
+  BoltMacroCall = 108,
-  JSFromKeyword = 111,
+  JSOperator = 111,
-  JSReturnKeyword = 112,
+  JSIdentifier = 112,
-  JSTryKeyword = 113,
+  JSString = 113,
-  JSFinallyKeyword = 114,
+  JSInteger = 114,
-  JSCatchKeyword = 115,
+  JSFromKeyword = 115,
-  JSImportKeyword = 116,
+  JSReturnKeyword = 116,
-  JSAsKeyword = 117,
+  JSTryKeyword = 117,
-  JSConstKeyword = 118,
+  JSFinallyKeyword = 118,
-  JSLetKeyword = 119,
+  JSCatchKeyword = 119,
-  JSExportKeyword = 120,
+  JSImportKeyword = 120,
-  JSFunctionKeyword = 121,
+  JSAsKeyword = 121,
-  JSWhileKeyword = 122,
+  JSConstKeyword = 122,
-  JSForKeyword = 123,
+  JSLetKeyword = 123,
-  JSCloseBrace = 124,
+  JSExportKeyword = 124,
-  JSCloseBracket = 125,
+  JSFunctionKeyword = 125,
-  JSCloseParen = 126,
+  JSWhileKeyword = 126,
-  JSOpenBrace = 127,
+  JSForKeyword = 127,
-  JSOpenBracket = 128,
+  JSCloseBrace = 128,
-  JSOpenParen = 129,
+  JSCloseBracket = 129,
-  JSSemi = 130,
+  JSCloseParen = 130,
-  JSComma = 131,
+  JSOpenBrace = 131,
-  JSDot = 132,
+  JSOpenBracket = 132,
-  JSDotDotDot = 133,
+  JSOpenParen = 133,
-  JSMulOp = 134,
+  JSSemi = 134,
-  JSAddOp = 135,
+  JSComma = 135,
-  JSDivOp = 136,
+  JSDot = 136,
-  JSSubOp = 137,
+  JSDotDotDot = 137,
-  JSLtOp = 138,
+  JSMulOp = 138,
-  JSGtOp = 139,
+  JSAddOp = 139,
-  JSBOrOp = 140,
+  JSDivOp = 140,
-  JSBXorOp = 141,
+  JSSubOp = 141,
-  JSBAndOp = 142,
+  JSLtOp = 142,
-  JSBNotOp = 143,
+  JSGtOp = 143,
-  JSNotOp = 144,
+  JSBOrOp = 144,
-  JSBindPattern = 146,
+  JSBXorOp = 145,
-  JSConstantExpression = 148,
+  JSBAndOp = 146,
-  JSMemberExpression = 149,
+  JSBNotOp = 147,
-  JSCallExpression = 150,
+  JSNotOp = 148,
-  JSBinaryExpression = 151,
+  JSBindPattern = 150,
-  JSUnaryExpression = 152,
+  JSConstantExpression = 152,
-  JSNewExpression = 153,
+  JSMemberExpression = 153,
-  JSSequenceExpression = 154,
+  JSCallExpression = 154,
-  JSConditionalExpression = 155,
+  JSBinaryExpression = 155,
-  JSLiteralExpression = 157,
+  JSUnaryExpression = 156,
-  JSReferenceExpression = 158,
+  JSNewExpression = 157,
-  JSCatchBlock = 162,
+  JSSequenceExpression = 158,
-  JSTryCatchStatement = 163,
+  JSConditionalExpression = 159,
-  JSExpressionStatement = 164,
+  JSLiteralExpression = 161,
-  JSConditionalCase = 165,
+  JSReferenceExpression = 162,
-  JSConditionalStatement = 166,
+  JSCatchBlock = 166,
-  JSReturnStatement = 167,
+  JSTryCatchStatement = 167,
-  JSParameter = 168,
+  JSExpressionStatement = 168,
-  JSImportStarBinding = 172,
+  JSConditionalCase = 169,
-  JSImportAsBinding = 173,
+  JSConditionalStatement = 170,
-  JSImportDeclaration = 174,
+  JSReturnStatement = 171,
-  JSFunctionDeclaration = 175,
+  JSParameter = 172,
-  JSArrowFunctionDeclaration = 176,
+  JSImportStarBinding = 176,
-  JSLetDeclaration = 177,
+  JSImportAsBinding = 177,
-  JSSourceFile = 178,
+  JSImportDeclaration = 178,
+  JSFunctionDeclaration = 179,
+  JSArrowFunctionDeclaration = 180,
+  JSLetDeclaration = 181,
+  JSSourceFile = 182,
 }
 
 
@@ -158,6 +167,7 @@ export function setParents(node: Syntax): void;
 export type SyntaxRange = [Syntax, Syntax];
 
 interface SyntaxBase<K extends SyntaxKind> {
+  id: number;
   kind: K;
   parentNode: ParentTypesOf<K> | null;
   span: TextSpan | null;
@@ -207,6 +217,7 @@ export type Token
   | BoltYieldKeyword
   | BoltMatchKeyword
   | BoltImportKeyword
+  | BoltExportKeyword
   | BoltPubKeyword
   | BoltModKeyword
   | BoltMutKeyword
@@ -304,6 +315,7 @@ export type BoltToken
   | BoltYieldKeyword
   | BoltMatchKeyword
   | BoltImportKeyword
+  | BoltExportKeyword
   | BoltPubKeyword
   | BoltModKeyword
   | BoltMutKeyword
@@ -426,6 +438,7 @@ export type BoltKeyword
   | BoltYieldKeyword
   | BoltMatchKeyword
   | BoltImportKeyword
+  | BoltExportKeyword
   | BoltPubKeyword
   | BoltModKeyword
   | BoltMutKeyword
@@ -480,6 +493,10 @@ export interface BoltImportKeyword extends SyntaxBase<SyntaxKind.BoltImportKeywo
   kind: SyntaxKind.BoltImportKeyword;
 }
 
+export interface BoltExportKeyword extends SyntaxBase<SyntaxKind.BoltExportKeyword> {
+  kind: SyntaxKind.BoltExportKeyword;
+}
+
 export interface BoltPubKeyword extends SyntaxBase<SyntaxKind.BoltPubKeyword> {
   kind: SyntaxKind.BoltPubKeyword;
 }
@@ -536,6 +553,7 @@ export interface BoltBracketed extends SyntaxBase<SyntaxKind.BoltBracketed> {
 export interface BoltSourceFile extends SyntaxBase<SyntaxKind.BoltSourceFile> {
   kind: SyntaxKind.BoltSourceFile;
   elements: BoltSourceElement[];
+  package: Package;
 }
 
 export interface BoltQualName extends SyntaxBase<SyntaxKind.BoltQualName> {
@@ -740,10 +758,8 @@ export interface BoltParameter extends SyntaxBase<SyntaxKind.BoltParameter> {
 }
 
 export type BoltDeclaration
-  = BoltModule
+  = BoltFunctionDeclaration
-  | BoltFunctionDeclaration
   | BoltVariableDeclaration
-  | BoltImportDeclaration
   | BoltTraitDeclaration
   | BoltImplDeclaration
   | BoltTypeAliasDeclaration
@@ -757,12 +773,12 @@ export type BoltTypeDeclaration
   | BoltRecordDeclaration
 
 
-export const enum BoltDeclarationModifiers {
+export const enum BoltModifiers {
-  Mutable = 1,Public = 2,IsType = 4,IsForeign = 8,}
+  IsMutable = 1,IsPublic = 2,}
 
 export interface BoltModule extends SyntaxBase<SyntaxKind.BoltModule> {
   kind: SyntaxKind.BoltModule;
-  modifiers: BoltDeclarationModifiers;
+  modifiers: BoltModifiers;
   name: BoltQualName;
   elements: BoltSourceElement[];
 }
@@ -779,7 +795,7 @@ export type BoltFunctionBodyElement
 
 export interface BoltFunctionDeclaration extends SyntaxBase<SyntaxKind.BoltFunctionDeclaration> {
   kind: SyntaxKind.BoltFunctionDeclaration;
-  modifiers: BoltDeclarationModifiers;
+  modifiers: BoltModifiers;
   target: string;
   name: BoltSymbol;
   params: BoltParameter[];
@@ -790,7 +806,7 @@ export interface BoltFunctionDeclaration extends SyntaxBase<SyntaxKind.BoltFunct
 
 export interface BoltVariableDeclaration extends SyntaxBase<SyntaxKind.BoltVariableDeclaration> {
   kind: SyntaxKind.BoltVariableDeclaration;
-  modifiers: BoltDeclarationModifiers;
+  modifiers: BoltModifiers;
   bindings: BoltPattern;
   type: BoltTypeExpression | null;
   value: BoltExpression | null;
@@ -805,15 +821,31 @@ export interface BoltPlainImportSymbol extends SyntaxBase<SyntaxKind.BoltPlainIm
   name: BoltQualName;
 }
 
-export interface BoltImportDeclaration extends SyntaxBase<SyntaxKind.BoltImportDeclaration> {
+export interface BoltImportDirective extends SyntaxBase<SyntaxKind.BoltImportDirective> {
-  kind: SyntaxKind.BoltImportDeclaration;
+  kind: SyntaxKind.BoltImportDirective;
+  modifiers: BoltModifiers;
   file: string;
   symbols: BoltImportSymbol[];
 }
 
+export interface BoltExportSymbol extends SyntaxBase<SyntaxKind.BoltExportSymbol> {
+  kind: SyntaxKind.BoltExportSymbol;
+}
+
+export interface BoltPlainExportSymbol extends SyntaxBase<SyntaxKind.BoltPlainExportSymbol> {
+  kind: SyntaxKind.BoltPlainExportSymbol;
+  name: BoltQualName;
+}
+
+export interface BoltExportDirective extends SyntaxBase<SyntaxKind.BoltExportDirective> {
+  kind: SyntaxKind.BoltExportDirective;
+  file: string;
+  symbols: BoltExportSymbol[] | null;
+}
+
 export interface BoltTraitDeclaration extends SyntaxBase<SyntaxKind.BoltTraitDeclaration> {
   kind: SyntaxKind.BoltTraitDeclaration;
-  modifiers: BoltDeclarationModifiers;
+  modifiers: BoltModifiers;
   name: BoltIdentifier;
   typeParams: BoltTypeParameter[] | null;
   elements: BoltDeclaration[];
@@ -821,7 +853,7 @@ export interface BoltTraitDeclaration extends SyntaxBase<SyntaxKind.BoltTraitDec
 
 export interface BoltImplDeclaration extends SyntaxBase<SyntaxKind.BoltImplDeclaration> {
   kind: SyntaxKind.BoltImplDeclaration;
-  modifiers: BoltDeclarationModifiers;
+  modifiers: BoltModifiers;
   name: BoltIdentifier;
   trait: BoltTypeExpression;
   typeParams: BoltTypeParameter[] | null;
@@ -830,7 +862,7 @@ export interface BoltImplDeclaration extends SyntaxBase<SyntaxKind.BoltImplDecla
 
 export interface BoltTypeAliasDeclaration extends SyntaxBase<SyntaxKind.BoltTypeAliasDeclaration> {
   kind: SyntaxKind.BoltTypeAliasDeclaration;
-  modifiers: BoltDeclarationModifiers;
+  modifiers: BoltModifiers;
   name: BoltIdentifier;
   typeParams: BoltTypeParameter[] | null;
   typeExpr: BoltTypeExpression;
@@ -849,7 +881,7 @@ export interface BoltRecordField extends SyntaxBase<SyntaxKind.BoltRecordField>
 
 export interface BoltRecordDeclaration extends SyntaxBase<SyntaxKind.BoltRecordDeclaration> {
   kind: SyntaxKind.BoltRecordDeclaration;
-  modifiers: BoltDeclarationModifiers;
+  modifiers: BoltModifiers;
   name: BoltIdentifier;
   typeParms: BoltTypeParameter[] | null;
   members: BoltRecordMember[] | null;
@@ -861,10 +893,8 @@ export type BoltSourceElement
   | BoltResumeStatement
   | BoltExpressionStatement
   | BoltMacroCall
-  | BoltModule
   | BoltFunctionDeclaration
   | BoltVariableDeclaration
-  | BoltImportDeclaration
   | BoltTraitDeclaration
   | BoltImplDeclaration
   | BoltTypeAliasDeclaration
@@ -873,6 +903,9 @@ export type BoltSourceElement
   | BoltTraitDeclaration
   | BoltTypeAliasDeclaration
   | BoltRecordDeclaration
+  | BoltModule
+  | BoltImportDirective
+  | BoltExportDirective
 
 
 export interface BoltMacroCall extends SyntaxBase<SyntaxKind.BoltMacroCall> {
@@ -1314,6 +1347,7 @@ export type BoltSyntax
   | BoltYieldKeyword
   | BoltMatchKeyword
   | BoltImportKeyword
+  | BoltExportKeyword
   | BoltPubKeyword
   | BoltModKeyword
   | BoltMutKeyword
@@ -1359,7 +1393,10 @@ export type BoltSyntax
   | BoltFunctionDeclaration
   | BoltVariableDeclaration
   | BoltPlainImportSymbol
-  | BoltImportDeclaration
+  | BoltImportDirective
+  | BoltExportSymbol
+  | BoltPlainExportSymbol
+  | BoltExportDirective
   | BoltTraitDeclaration
   | BoltImplDeclaration
   | BoltTypeAliasDeclaration
@@ -1467,6 +1504,7 @@ export type Syntax
   | BoltYieldKeyword
   | BoltMatchKeyword
   | BoltImportKeyword
+  | BoltExportKeyword
   | BoltPubKeyword
   | BoltModKeyword
   | BoltMutKeyword
@@ -1512,7 +1550,10 @@ export type Syntax
   | BoltFunctionDeclaration
   | BoltVariableDeclaration
   | BoltPlainImportSymbol
-  | BoltImportDeclaration
+  | BoltImportDirective
+  | BoltExportSymbol
+  | BoltPlainExportSymbol
+  | BoltExportDirective
   | BoltTraitDeclaration
   | BoltImplDeclaration
   | BoltTypeAliasDeclaration
@@ -1618,6 +1659,7 @@ export function createBoltLoopKeyword(span?: TextSpan | null): BoltLoopKeyword;
 export function createBoltYieldKeyword(span?: TextSpan | null): BoltYieldKeyword;
 export function createBoltMatchKeyword(span?: TextSpan | null): BoltMatchKeyword;
 export function createBoltImportKeyword(span?: TextSpan | null): BoltImportKeyword;
+export function createBoltExportKeyword(span?: TextSpan | null): BoltExportKeyword;
 export function createBoltPubKeyword(span?: TextSpan | null): BoltPubKeyword;
 export function createBoltModKeyword(span?: TextSpan | null): BoltModKeyword;
 export function createBoltMutKeyword(span?: TextSpan | null): BoltMutKeyword;
@@ -1629,7 +1671,7 @@ export function createBoltImplKeyword(span?: TextSpan | null): BoltImplKeyword;
 export function createBoltParenthesized(text: string, span?: TextSpan | null): BoltParenthesized;
 export function createBoltBraced(text: string, span?: TextSpan | null): BoltBraced;
 export function createBoltBracketed(text: string, span?: TextSpan | null): BoltBracketed;
-export function createBoltSourceFile(elements: BoltSourceElement[], span?: TextSpan | null): BoltSourceFile;
+export function createBoltSourceFile(elements: BoltSourceElement[], package: Package, span?: TextSpan | null): BoltSourceFile;
 export function createBoltQualName(modulePath: BoltIdentifier[] | null, name: BoltSymbol, span?: TextSpan | null): BoltQualName;
 export function createBoltReferenceTypeExpression(name: BoltQualName, arguments: BoltTypeExpression[] | null, span?: TextSpan | null): BoltReferenceTypeExpression;
 export function createBoltFunctionTypeExpression(params: BoltParameter[], returnType: BoltTypeExpression | null, span?: TextSpan | null): BoltFunctionTypeExpression;
@@ -1659,16 +1701,19 @@ export function createBoltConditionalStatement(cases: BoltConditionalCase[], spa
 export function createBoltResumeStatement(value: BoltExpression, span?: TextSpan | null): BoltResumeStatement;
 export function createBoltExpressionStatement(expression: BoltExpression, span?: TextSpan | null): BoltExpressionStatement;
 export function createBoltParameter(index: number, bindings: BoltPattern, type: BoltTypeExpression | null, defaultValue: BoltExpression | null, span?: TextSpan | null): BoltParameter;
-export function createBoltModule(modifiers: BoltDeclarationModifiers, name: BoltQualName, elements: BoltSourceElement[], span?: TextSpan | null): BoltModule;
+export function createBoltModule(modifiers: BoltModifiers, name: BoltQualName, elements: BoltSourceElement[], span?: TextSpan | null): BoltModule;
-export function createBoltFunctionDeclaration(modifiers: BoltDeclarationModifiers, target: string, name: BoltSymbol, params: BoltParameter[], returnType: BoltTypeExpression | null, typeParams: BoltTypeParameter[] | null, body: BoltFunctionBodyElement[], span?: TextSpan | null): BoltFunctionDeclaration;
+export function createBoltFunctionDeclaration(modifiers: BoltModifiers, target: string, name: BoltSymbol, params: BoltParameter[], returnType: BoltTypeExpression | null, typeParams: BoltTypeParameter[] | null, body: BoltFunctionBodyElement[], span?: TextSpan | null): BoltFunctionDeclaration;
-export function createBoltVariableDeclaration(modifiers: BoltDeclarationModifiers, bindings: BoltPattern, type: BoltTypeExpression | null, value: BoltExpression | null, span?: TextSpan | null): BoltVariableDeclaration;
+export function createBoltVariableDeclaration(modifiers: BoltModifiers, bindings: BoltPattern, type: BoltTypeExpression | null, value: BoltExpression | null, span?: TextSpan | null): BoltVariableDeclaration;
 export function createBoltPlainImportSymbol(name: BoltQualName, span?: TextSpan | null): BoltPlainImportSymbol;
-export function createBoltImportDeclaration(file: string, symbols: BoltImportSymbol[], span?: TextSpan | null): BoltImportDeclaration;
+export function createBoltImportDirective(modifiers: BoltModifiers, file: string, symbols: BoltImportSymbol[], span?: TextSpan | null): BoltImportDirective;
-export function createBoltTraitDeclaration(modifiers: BoltDeclarationModifiers, name: BoltIdentifier, typeParams: BoltTypeParameter[] | null, elements: BoltDeclaration[], span?: TextSpan | null): BoltTraitDeclaration;
+export function createBoltExportSymbol(span?: TextSpan | null): BoltExportSymbol;
-export function createBoltImplDeclaration(modifiers: BoltDeclarationModifiers, name: BoltIdentifier, trait: BoltTypeExpression, typeParams: BoltTypeParameter[] | null, elements: BoltDeclaration[], span?: TextSpan | null): BoltImplDeclaration;
+export function createBoltPlainExportSymbol(name: BoltQualName, span?: TextSpan | null): BoltPlainExportSymbol;
-export function createBoltTypeAliasDeclaration(modifiers: BoltDeclarationModifiers, name: BoltIdentifier, typeParams: BoltTypeParameter[] | null, typeExpr: BoltTypeExpression, span?: TextSpan | null): BoltTypeAliasDeclaration;
+export function createBoltExportDirective(file: string, symbols: BoltExportSymbol[] | null, span?: TextSpan | null): BoltExportDirective;
+export function createBoltTraitDeclaration(modifiers: BoltModifiers, name: BoltIdentifier, typeParams: BoltTypeParameter[] | null, elements: BoltDeclaration[], span?: TextSpan | null): BoltTraitDeclaration;
+export function createBoltImplDeclaration(modifiers: BoltModifiers, name: BoltIdentifier, trait: BoltTypeExpression, typeParams: BoltTypeParameter[] | null, elements: BoltDeclaration[], span?: TextSpan | null): BoltImplDeclaration;
+export function createBoltTypeAliasDeclaration(modifiers: BoltModifiers, name: BoltIdentifier, typeParams: BoltTypeParameter[] | null, typeExpr: BoltTypeExpression, span?: TextSpan | null): BoltTypeAliasDeclaration;
 export function createBoltRecordField(name: BoltIdentifier, type: BoltTypeExpression, span?: TextSpan | null): BoltRecordField;
-export function createBoltRecordDeclaration(modifiers: BoltDeclarationModifiers, name: BoltIdentifier, typeParms: BoltTypeParameter[] | null, members: BoltRecordMember[] | null, span?: TextSpan | null): BoltRecordDeclaration;
+export function createBoltRecordDeclaration(modifiers: BoltModifiers, name: BoltIdentifier, typeParms: BoltTypeParameter[] | null, members: BoltRecordMember[] | null, span?: TextSpan | null): BoltRecordDeclaration;
 export function createBoltMacroCall(name: BoltIdentifier, text: string, span?: TextSpan | null): BoltMacroCall;
 export function createJSOperator(text: string, span?: TextSpan | null): JSOperator;
 export function createJSIdentifier(text: string, span?: TextSpan | null): JSIdentifier;
@@ -1772,6 +1817,7 @@ export function isBoltLoopKeyword(value: any): value is BoltLoopKeyword;
 export function isBoltYieldKeyword(value: any): value is BoltYieldKeyword;
 export function isBoltMatchKeyword(value: any): value is BoltMatchKeyword;
 export function isBoltImportKeyword(value: any): value is BoltImportKeyword;
+export function isBoltExportKeyword(value: any): value is BoltExportKeyword;
 export function isBoltPubKeyword(value: any): value is BoltPubKeyword;
 export function isBoltModKeyword(value: any): value is BoltModKeyword;
 export function isBoltMutKeyword(value: any): value is BoltMutKeyword;
@@ -1826,7 +1872,10 @@ export function isBoltFunctionDeclaration(value: any): value is BoltFunctionDecl
 export function isBoltVariableDeclaration(value: any): value is BoltVariableDeclaration;
 export function isBoltImportSymbol(value: any): value is BoltImportSymbol;
 export function isBoltPlainImportSymbol(value: any): value is BoltPlainImportSymbol;
-export function isBoltImportDeclaration(value: any): value is BoltImportDeclaration;
+export function isBoltImportDirective(value: any): value is BoltImportDirective;
+export function isBoltExportSymbol(value: any): value is BoltExportSymbol;
+export function isBoltPlainExportSymbol(value: any): value is BoltPlainExportSymbol;
+export function isBoltExportDirective(value: any): value is BoltExportDirective;
 export function isBoltTraitDeclaration(value: any): value is BoltTraitDeclaration;
 export function isBoltImplDeclaration(value: any): value is BoltImplDeclaration;
 export function isBoltTypeAliasDeclaration(value: any): value is BoltTypeAliasDeclaration;

src/bin/bolt.ts

@@ -7,11 +7,17 @@ import { sync as globSync } from "glob"
 import * as path from "path"
 import * as fs from "fs"
 import yargs from "yargs"
+import yaml from "js-yaml"
+import semver from "semver"
 
 import { Program } from "../program"
 import { parseSourceFile } from "../parser"
-import { BoltSourceFile} from "../ast"
 import { Frontend } from "../frontend"
+import { Package } from "../common"
+import {hasOwnProperty} from "../util"
+import {isString} from "util"
+import {DiagnosticPrinter, E_FIELD_NOT_PRESENT, E_FIELD_MUST_BE_STRING, E_FIELD_HAS_INVALID_VERSION_NUMBER} from "../diagnostics"
+import {BoltSourceFileModifiers} from "../ast"
 
 //global.print = function (value: any) {
 //  console.error(require('util').inspect(value, { depth: Infinity, colors: true }))
@@ -43,16 +49,99 @@ function flatMap<T>(array: T[], proc: (element: T) => T[]) {
   return out
 }
 
-function loadAllSourceFiles(filenames: string[]): BoltSourceFile[] {
+const diagnostics = new DiagnosticPrinter();
-  const sourceFiles = [];
+
+function loadPackageMetadata(rootDir: string) {
+
+  let name = null
+  let version = null;
+
+  let hasVersionErrors = false;
+  let hasNameErrors = false;
+
+  const filepath = path.join(rootDir, 'Boltfile');
+  if (fs.existsSync(filepath)) {
+    const data = yaml.safeLoad(fs.readFileSync(filepath, 'utf8'));
+    if (data !== undefined) {
+      if (hasOwnProperty(data, 'name')) {
+        if (!isString(data.name)) {
+          diagnostics.add({
+            message: E_FIELD_MUST_BE_STRING,
+            severity: 'error',
+            args: { name: 'name' },
+          });
+          hasNameErrors = true;
+        } else {
+          name = data.name;
+        }
+      }
+      if (hasOwnProperty(data, 'version')) {
+        if (!isString(data.version)) {
+          diagnostics.add({
+            message: E_FIELD_MUST_BE_STRING,
+            args: { name: 'version' },
+            severity: 'error',
+          });
+          hasVersionErrors = true;
+        } else {
+          if (!semver.valid(data.version)) {
+            diagnostics.add({
+              message: E_FIELD_HAS_INVALID_VERSION_NUMBER,
+              args: { name: 'version' },
+              severity: 'error',
+            });
+            hasVersionErrors = true;
+          } else {
+            version = data.version;
+          }
+        }
+      }
+    }
+  }
+
+  if (name === null && !hasNameErrors) {
+    diagnostics.add({
+      message: E_FIELD_NOT_PRESENT,
+      severity: 'warning',
+      args: { name: 'name' },
+    });
+  }
+
+  if (version === null && !hasVersionErrors) {
+    diagnostics.add({
+      message: E_FIELD_NOT_PRESENT,
+      severity: 'warning',
+      args: { name: 'version' },
+    });
+  }
+
+  return {
+    name,
+    version
+  };
+
+}
+
+function loadPackage(rootDir: string): Package {
+  const data = loadPackageMetadata(rootDir);
+  const pkg = new Package(rootDir, data.name, data.version, []);
+  for (const filepath of globSync(path.join(rootDir, '**/*.bolt'))) {
+    pkg.addSourceFile(parseSourceFile(filepath, pkg));
+  }
+  return pkg;
+}
+
+function loadPackagesAndSourceFiles(filenames: string[], cwd = '.'): Package[] {
+  const anonPkg = new Package(cwd, null, null, []);
+  const pkgs = [ anonPkg ];
   for (const filename of filenames) {
     if (fs.statSync(filename).isDirectory()) {
-      for (const filepath of globSync(path.join(filename, '**/*.bolt'))) {
+      pkgs.push(loadPackage(filename));
-        sourceFiles.push(parseSourceFile(filepath));
+    } else {
+      anonPkg.addSourceFile(parseSourceFile(filename, anonPkg, 0));
     }
   }
-  }
+  return pkgs;
-  return sourceFiles;
 }
 
 yargs
@@ -90,8 +179,8 @@ yargs
 
     , args => {
 
-      const sourceFiles = loadAllSourceFiles(toArray(args.files as string[] | string));
+      const pkgs = loadPackagesAndSourceFiles(toArray(args.files as string[] | string));
-      const program = new Program(sourceFiles);
+      const program = new Program(pkgs);
       const frontend = new Frontend();
       frontend.typeCheck(program);
       if (frontend.diagnostics.hasErrors && !args.force) {

src/checker.ts

@@ -24,13 +24,13 @@
  */
 
 import {
+  isSyntax,
   Syntax,
   SyntaxKind,
   BoltReferenceExpression,
   BoltDeclaration,
   BoltSourceFile,
   BoltSyntax,
-  BoltReferenceTypeExpression,
   BoltTypeDeclaration,
   BoltExpression,
   BoltFunctionDeclaration,
@@ -40,9 +40,11 @@ import {
   BoltTypeExpression,
   BoltSourceElement,
   isBoltStatement,
-  isBoltDeclaration
+  isBoltDeclaration,
+  isSourceFile,
+  BoltReferenceTypeExpression
 } from "./ast";
-import {FastStringMap, memoize, assert} from "./util";
+import {FastStringMap, memoize, assert, verbose} from "./util";
 import {
   DiagnosticPrinter,
   E_TYPES_NOT_ASSIGNABLE,
@@ -53,15 +55,13 @@ import {
   E_INVALID_ARGUMENTS
 } from "./diagnostics";
 import { createAnyType, isOpaqueType, createOpaqueType, Type, createVoidType, createVariantType, isVoidType } from "./types";
-import { getReturnStatementsInFunctionBody } from "./common";
+import { getReturnStatementsInFunctionBody, isAutoImported, toDeclarationPath, createDeclarationPath, hasRelativeModulePath, hasAbsoluteModulePath, DeclarationPath, getModulePath, getSymbolNameOfDeclarationPath } from "./common";
 import {emit} from "./emitter";
 
-interface SymbolInfo {
+const PACKAGE_SCOPE_ID = 0;
-  declarations: BoltDeclaration[];
-}
 
-interface TypeSymbolInfo {
+interface SymbolInfo<N extends Syntax> {
-  declarations: BoltTypeDeclaration[];
+  declarations: N[];
 }
 
 function introducesNewScope(kind: SyntaxKind): boolean {
@@ -79,12 +79,120 @@ function introducesNewTypeScope(kind: SyntaxKind): boolean {
 type Scope = unknown;
 type TypeScope = unknown;
 
+function getScopeId(scope: Scope | TypeScope) {
+  if (isSyntax(scope)) {
+    return scope.id;
+  }
+  return PACKAGE_SCOPE_ID;
+}
+
 function createSymbol(node: BoltDeclaration): SymbolInfo {
   return { declarations: [ node ] };
 }
 
-function createTypeSymbol(node: BoltTypeDeclaration): TypeSymbolInfo {
+class SymbolResolver<N extends Syntax> {
-  return { declarations: [ node ] };
+
+  private symbols = new FastStringMap<string, SymbolInfo<N>>();
+
+  constructor(private introducesNewScope: (kind: SyntaxKind) => boolean) {
+
+  }
+
+  public addSymbol(name: string, node: N): void {
+    const scope = this.getScopeSurroundingNode(node)
+    verbose(`Adding symbol ${name} in scope #${getScopeId(scope)}`);
+    const sym = { declarations: [ node ] };
+    this.symbols.set(`${name}@${getScopeId(scope)}`, sym);
+  }
+
+  public getParentScope(scope: Scope): Scope | null {
+    if (!isSyntax(scope)) {
+      // Scope is the global package scope
+      return null;
+    }
+    if (scope.kind === SyntaxKind.BoltSourceFile) {
+      return scope.package;
+    }
+    return this.getScopeForNode(scope.parentNode!)
+  }
+
+  public getScopeSurroundingNode(node: Syntax): Scope {
+    assert(node.parentNode !== null);
+    return this.getScopeForNode(node.parentNode!);
+  }
+
+  public getScopeForNode(node: Syntax): Scope {
+    let currNode = node;
+    while (!this.introducesNewScope(currNode.kind)) {
+      if (currNode.kind === SyntaxKind.BoltSourceFile) {
+        return currNode.package;
+      }
+      currNode = currNode.parentNode!;
+    }
+    return currNode;
+  }
+
+  private lookupSymbolInScope(name: string, scope: Scope): SymbolInfo<N> | null {
+    const key = `${name}@${getScopeId(scope)}`;
+    if (!this.symbols.has(key)) {
+      return null;
+    }
+    return this.symbols.get(key);
+  }
+
+  public findSymbolInScopeOf(name: string, scope: Scope): SymbolInfo<N> | null {
+    while (true) {
+      const sym = this.lookupSymbolInScope(name, scope);
+      if (sym !== null) {
+        return sym;
+      }
+      const parentScope = this.getParentScope(scope);
+      if (parentScope === null) {
+        break;
+      }
+      scope = parentScope;
+    }
+    return null;
+  }
+
+  public resolve(path: DeclarationPath, node: BoltSyntax): BoltSyntax | null {
+    let scope = this.getScopeSurroundingNode(node);
+    if (hasAbsoluteModulePath(path)) {
+      // TODO
+    } else if (hasRelativeModulePath(path)) {
+      while (true) {
+        let shouldSearchParentScopes = false;
+        let currScope = scope;
+        for (const name of getModulePath(path)) {
+          const sym = this.lookupSymbolInScope(name, currScope);
+          if (sym === null) {
+            shouldSearchParentScopes = true;
+            break;
+          }
+          if (sym.declarations[0].kind !== SyntaxKind.BoltModule) {
+            shouldSearchParentScopes = true;
+            break;
+          }
+          currScope = this.getScopeForNode(sym.declarations[0]);
+        }
+        if (!shouldSearchParentScopes) {
+          scope = currScope;
+          break;
+        }
+        const parentScope = this.getParentScope(scope);
+        if (parentScope === null) {
+          return null;
+        }
+        scope = parentScope;
+      }
+    }
+    const sym = this.findSymbolInScopeOf(getSymbolNameOfDeclarationPath(path), scope);
+    if (sym === null) {
+      return null;
+    }
+    return sym.declarations[0]!;
+  }
+
 }
 
 export class TypeChecker {
@@ -93,8 +201,8 @@ export class TypeChecker {
 
   }
 
-  private symbols = new FastStringMap<string, SymbolInfo>();
+  private varResolver = new SymbolResolver<BoltDeclaration>(introducesNewScope);
-  private typeSymbols = new FastStringMap<string, TypeSymbolInfo>();
+  private typeResolver = new SymbolResolver<BoltTypeDeclaration>(introducesNewTypeScope);
 
   public checkSourceFile(node: BoltSourceFile): void {
 
@@ -107,12 +215,15 @@ export class TypeChecker {
 
       switch (node.kind) {
 
+        case SyntaxKind.BoltConstantExpression:
+          break;
+
         case SyntaxKind.BoltReferenceExpression:
         {
           if (self.resolveReferenceExpression(node) === null) {
             self.diagnostics.add({
               message: E_DECLARATION_NOT_FOUND,
-              args: { name: node.name.name.text },
+              args: { name: emit(node.name.name) },
               severity: 'error',
               node: node,
             })
@@ -186,7 +297,7 @@ export class TypeChecker {
           if (self.resolveTypeReferenceExpression(node) === null) {
             self.diagnostics.add({
               message: E_TYPE_DECLARATION_NOT_FOUND,
-              args: { name: node.name.name.text },
+              args: { name: emit(node.name.name) },
               severity: 'error',
               node: node,
             })
@@ -338,15 +449,19 @@ export class TypeChecker {
         visitStatement(node);
       } else if (isBoltDeclaration(node)) {
         visitDeclaration(node);
-      } else {
+      } else if (node.kind === SyntaxKind.BoltModule) {
-        throw new Error(`Unknown node of kind ${kindToString(node)}`);
+        for (const element of node.elements) {
+          visitSourceElement(element);
+        }
+      } else if (node.kind !== SyntaxKind.BoltImportDirective) {
+        throw new Error(`Unknown node of kind ${kindToString(node.kind)}`);
       }
     }
 
   }
 
   private resolveType(name: string, node: BoltSyntax): Type | null {
-    const sym = this.findSymbolInTypeScopeOf(name, this.getTypeScopeSurroundingNode(node))
+    const sym = this.typeResolver.findSymbolInScopeOf(name, this.typeResolver.getScopeSurroundingNode(node))
     if (sym === null) {
       return null;
     }
@@ -429,11 +544,13 @@ export class TypeChecker {
     function visitExpression(node: BoltExpression) {
       switch (node.kind) {
         case SyntaxKind.BoltReferenceExpression:
+        {
           const resolved = self.resolveReferenceExpression(node);
           if (resolved !== null) {
             visitFunctionBodyElement(resolved);
           }
           break;
+        }
         default:
           throw new Error(`Unexpected node type ${kindToString(node.kind)}`);
       }
@@ -475,182 +592,25 @@ export class TypeChecker {
 
       case SyntaxKind.BoltFunctionDeclaration:
       {
-        const scope = this.getScopeSurroundingNode(node);
+        this.varResolver.addSymbol(emit(node.name), node);
-        const sym = createSymbol(node);
-        this.addSymbol(emit(node.name), scope, sym);
         break;
       }
 
       case SyntaxKind.BoltRecordDeclaration:
       {
-        const typeScope = this.getTypeScopeSurroundingNode(node);
+        this.typeResolver.addSymbol(node.name.text, node);
-        const typeSym = createTypeSymbol(node);
-        this.addTypeSymbol(node.name.text, typeScope, typeSym);
       }
 
     }
 
   }
 
-  private addSymbol(name: string, scope: Scope, sym: SymbolInfo): void {
+  private resolveReferenceExpression(node: BoltReferenceExpression): BoltDeclaration | null {
-    console.error(`Adding symbol ${name}`);
+    return this.varResolver.resolve(createDeclarationPath(node.name), node);
-    this.symbols.set(`${name}@${(scope as any).id}`, sym);
   }
 
-  private addTypeSymbol(name: string, scope: TypeScope, sym: TypeSymbolInfo): void {
+  private resolveTypeReferenceExpression(node: BoltReferenceTypeExpression): BoltTypeDeclaration | null {
-    console.error(`Adding type symbol ${name}`);
+    return this.typeResolver.resolve(createDeclarationPath(node.name), node);
-    this.typeSymbols.set(`${name}@${(scope as any).id}`, sym);
-  }
-
-  public getParentScope(scope: Scope): Scope | null {
-    let node = scope as Syntax;
-    if (node.kind === SyntaxKind.BoltSourceFile) {
-      return null;
-    }
-    node = node.parentNode!;
-    while (!introducesNewScope(node.kind)) {
-      node = node.parentNode!;
-    }
-    return node;
-  }
-
-  public getParentTypeScope(scope: TypeScope): TypeScope | null {
-    let node = scope as Syntax;
-    if (node.kind === SyntaxKind.BoltSourceFile) {
-      return null;
-    }
-    node = node.parentNode!;
-    while (!introducesNewTypeScope(node.kind)) {
-      node = node.parentNode!;
-    }
-    return node;
-  }
-
-  private getScopeSurroundingNode(node: Syntax): Scope {
-    if (node.kind === SyntaxKind.BoltSourceFile) {
-      return node;
-    }
-    return this.getScopeForNode(node.parentNode);
-  }
-
-  private getTypeScopeSurroundingNode(node: Syntax): TypeScope {
-    if (node.kind === SyntaxKind.BoltSourceFile) {
-      return node;
-    }
-    return this.getScopeForNode(node.parentNode);
-  }
-
-  private getScopeForNode(node: Syntax): Scope {
-    if (node.kind === SyntaxKind.BoltSourceFile) {
-      return node;
-    }
-    let currNode = node;
-    while (!introducesNewScope(currNode.kind)) {
-      currNode = currNode.parentNode!;
-    }
-    return currNode;
-  }
-
-  private getTypeScopeForNode(node: Syntax): TypeScope {
-    if (node.kind === SyntaxKind.BoltSourceFile) {
-      return node;
-    }
-    let currNode = node;
-    while (!introducesNewTypeScope(currNode.kind)) {
-      currNode = currNode.parentNode!;
-    }
-    return currNode;
-  }
-
-  private lookupSymbolInScope(name: string, scope: Scope): SymbolInfo | null {
-    const key = `${name}@${(scope as any).id}`;
-    if (!this.symbols.has(key)) {
-      return null;
-    }
-    return this.symbols.get(key);
-  }
-
-  private lookupSymbolInTypeScope(name: string, scope: TypeScope): TypeSymbolInfo | null {
-    const key = `${name}@${(scope as any).id}`;
-    if (!this.typeSymbols.has(key)) {
-      return null;
-    }
-    return this.typeSymbols.get(key);
-  }
-
-  public findSymbolInScopeOf(name: string, scope: Scope): SymbolInfo | null {
-    while (true) {
-      const sym = this.lookupSymbolInScope(name, scope);
-      if (sym !== null) {
-        return sym;
-      }
-      const parentScope = this.getParentScope(scope);
-      if (parentScope === null) {
-        break;
-      }
-      scope = parentScope;
-    }
-    return null;
-  }
-
-  public findSymbolInTypeScopeOf(name: string, scope: TypeScope): TypeSymbolInfo | null {
-    while (true) {
-      const sym = this.lookupSymbolInTypeScope(name, scope);
-      if (sym !== null) {
-        return sym;
-      }
-      const parentTypeScope = this.getParentTypeScope(scope);
-      if (parentTypeScope === null) {
-        break;
-      }
-      scope = parentTypeScope;
-    }
-    return null;
-  }
-
-  public resolveReferenceExpression(node: BoltReferenceExpression): BoltDeclaration | null {
-    let scope = this.getScopeSurroundingNode(node);
-    if (node.name.modulePath !== null) {
-      while (true) {
-        let shouldSearchParentScopes = false;
-        let currScope = scope;
-        for (const name of node.name.modulePath) {
-          const sym = this.lookupSymbolInScope(name.text, currScope);
-          if (sym === null) {
-            shouldSearchParentScopes = true;
-            break;
-          }
-          if (sym.declarations[0].kind !== SyntaxKind.BoltModule) {
-            shouldSearchParentScopes = true;
-            break;
-          }
-          currScope = this.getScopeForNode(sym.declarations[0]);
-        }
-        if (!shouldSearchParentScopes) {
-          scope = currScope;
-          break;
-        }
-        const parentScope = this.getParentScope(scope);
-        if (parentScope === null) {
-          return null;
-        }
-        scope = parentScope;
-      }
-    }
-    const sym = this.findSymbolInScopeOf(emit(node.name.name), scope);
-    if (sym === null) {
-      return null;
-    }
-    return sym.declarations[0]!;
-  }
-
-  public resolveTypeReferenceExpression(node: BoltReferenceTypeExpression): BoltTypeDeclaration | null {
-    const typeScope = this.getTypeScopeSurroundingNode(node);
-    const typeSym = this.findSymbolInTypeScopeOf(emit(node.name.name), typeScope);
-    if (typeSym === null) {
-      return null;
-    }
-    return typeSym.declarations[0]!;
   }
 
 }

src/common.ts

@@ -7,7 +7,10 @@ import {
   kindToString,
   Syntax,
   Token,
-  isBoltPunctuated
+  isBoltPunctuated,
+  SourceFile,
+  BoltSourceFile,
+  BoltSourceFileModifiers
 } from "./ast";
 import { BOLT_SUPPORTED_LANGUAGES } from "./constants"
 import {emit} from "./emitter";
@@ -15,6 +18,30 @@ import {FastStringMap, enumerate, escapeChar} from "./util";
 import {TextSpan, TextPos, TextFile} from "./text";
 import {Scanner} from "./scanner";
 
+export class Package {
+
+  constructor(
+    public rootDir: string,
+    public name: string | null,
+    public version: string | null,
+    public sourceFiles: SourceFile[],
+  ) {
+
+  }
+
+  public addSourceFile(sourceFile: SourceFile) {
+    this.sourceFiles.push(sourceFile);
+  }
+
+}
+
+export function isAutoImported(node: BoltSourceFile): boolean {
+  //if (node.kind !== SyntaxKind.BoltSourceFile) {
+  //  node = node.getParentOfKind(SyntaxKind.BoltSourceFile)!
+  //}
+  return (node.modifiers & BoltSourceFileModifiers.AutoImport) > 0;
+}
+
 export function getLanguage(node: Syntax): string {
   const kindStr = kindToString(node.kind);
   for (const prefix of BOLT_SUPPORTED_LANGUAGES) {
@@ -164,6 +191,10 @@ export class OperatorTable {
 
 export function describeKind(kind: SyntaxKind): string {
   switch (kind) {
+    case SyntaxKind.BoltImportKeyword:
+      return "'import'";
+    case SyntaxKind.BoltExportKeyword:
+      return "'export'";
     case SyntaxKind.BoltExMark:
       return "'!'";
     case SyntaxKind.JSIdentifier:
@@ -257,7 +288,7 @@ export function describeKind(kind: SyntaxKind): string {
     case SyntaxKind.BoltTraitKeyword:
       return "'impl'";
     case SyntaxKind.BoltImplKeyword:
-      return "'trait'";
+      return "'impl'";
     case SyntaxKind.BoltForKeyword:
       return "'for'";
     case SyntaxKind.JSMulOp:
@@ -297,11 +328,37 @@ export function describeKind(kind: SyntaxKind): string {
   }
 }
 
-export function toDeclarationPath(node: BoltQualName): string[] {
+export type DeclarationPath = unknown;
-  const lastElement = emit(node.name);
+
-  if (node.modulePath === null) {
+type DeclarationPathInfo = {
-    return [ lastElement ];
+  modulePath: string[],
-  }
+  isAbsolute: boolean,
-  return [...node.modulePath.map(id => id.text), lastElement];
+  name: string
+};
+
+export function getModulePath(path: DeclarationPath): string[] {
+  return (path as DeclarationPathInfo).modulePath;
+}
+
+export function hasAbsoluteModulePath(path: DeclarationPath): boolean {
+  return (path as DeclarationPathInfo).modulePath.length > 0 
+      && (path as DeclarationPathInfo).isAbsolute;
+}
+
+export function hasRelativeModulePath(path: DeclarationPath): boolean {
+  return (path as DeclarationPathInfo).modulePath.length > 0
+     && !(path as DeclarationPathInfo).isAbsolute;
+}
+
+export function getSymbolNameOfDeclarationPath(path: DeclarationPath): string {
+  return (path as DeclarationPathInfo).name;
+}
+
+export function createDeclarationPath(node: BoltQualName): DeclarationPath {
+  const name = emit(node.name);
+  if (node.modulePath === null) {
+    return { modulePath: [], isAbsolute: false, name };
+  }
+  return { modulePath: node.modulePath.map(id => id.text), isAbsolute: false, name };
 }
 

src/diagnostics.ts

@@ -3,6 +3,9 @@ import chalk from "chalk"
 import {Syntax} from "./ast";
 import {format, MapLike, FormatArg} from "./util";
 
+export const E_FIELD_HAS_INVALID_VERSION_NUMBER = "Field '{name}' contains an invalid version nunmber."
+export const E_FIELD_MUST_BE_STRING = "Field '{name}' must be a string."
+export const E_FIELD_NOT_PRESENT = "Field '{name}' is not present."
 export const E_TYPE_DECLARATION_NOT_FOUND = "A type declaration named '{name}' was not found."
 export const E_DECLARATION_NOT_FOUND = "Reference to an undefined declaration '{name}'.";
 export const E_TYPES_NOT_ASSIGNABLE = "Types {left} and {right} are not assignable.";
@@ -84,6 +87,9 @@ export class DiagnosticPrinter {
       case 'error':
         this.hasErrors = true;
         out += chalk.bold.red('error: ');
+      case 'warning':
+        this.hasErrors = true;
+        out += chalk.bold.red('warning: ');
     }
     if (diagnostic.args !== undefined) {
       out += format(diagnostic.message, diagnostic.args) + '\n';

src/frontend.ts

@@ -8,7 +8,7 @@ import { Program } from "./program"
 import { TypeChecker } from "./checker"
 import { Evaluator } from "./evaluator"
 import { emit } from "./emitter"
-import { Syntax, BoltSourceFile } from "./ast"
+import { Syntax, BoltSourceFile, SourceFile } from "./ast"
 import { upsearchSync, FastStringMap, getFileStem, getLanguage } from "./util"
 import { Package } from "./package"
 import { verbose, memoize } from "./util"
@@ -115,18 +115,13 @@ export class Frontend {
     }
 
     for (const sourceFile of program.getAllSourceFiles()) {
-      //const filepath = rootNode.span!.file.fullPath;
-      //const pkg = this.getPackage(filepath);
-      //if (pkg !== null) {
-      //
-      //}
       fs.mkdirp('.bolt-work');
       fs.writeFileSync(this.mapToTargetFile(sourceFile), emit(sourceFile), 'utf8');
     }
 
   }
 
-  private mapToTargetFile(node: Syntax) {
+  private mapToTargetFile(node: SourceFile) {
     return path.join('.bolt-work', getFileStem(node.span!.file.fullPath) + getDefaultExtension(getLanguage(node)));
   }
 

src/package.ts

@@ -1,9 +0,0 @@
-
-export class Package {
-
-  constructor(public rootDir: string) {
-
-  }
-
-}
-

src/parser.ts

@@ -16,7 +16,7 @@ import {
   BoltQualName,
   BoltPattern,
   createBoltBindPattern,
-  BoltImportDeclaration,
+  BoltImportDirective,
   BoltTypeExpression,
   createBoltReferenceTypeExpression,
   createBoltConstantExpression,
@@ -25,8 +25,8 @@ import {
   BoltBindPattern,
   createBoltRecordDeclaration,
   createBoltRecordField,
-  createBoltImportDeclaration,
+  createBoltImportDirective,
-  BoltDeclarationModifiers,
+  BoltModifiers,
   BoltStringLiteral,
   BoltImportSymbol,
   BoltExpressionStatement,
@@ -77,6 +77,7 @@ import {
   BoltMacroCall,
   createBoltMacroCall,
   createBoltMemberExpression,
+  BoltSourceFileModifiers,
 } from "./ast"
 
 import { parseForeignLanguage } from "./foreign"
@@ -88,6 +89,7 @@ import {
   ParseError,
   setOrigNodeRange,
   createTokenStream,
+  Package,
 } from "./common"
 import { Stream, uniq } from "./util"
 
@@ -140,6 +142,7 @@ const KIND_DECLARATION_T0 = uniq([
 
 const KIND_SOURCEELEMENT_T0 = uniq([
   SyntaxKind.BoltModKeyword,
+  SyntaxKind.BoltImportKeyword,
   ...KIND_EXPRESSION_T0,
   ...KIND_STATEMENT_T0,
   ...KIND_DECLARATION_T0,
@@ -321,7 +324,13 @@ export class Parser {
     }
   }
 
-  public parseImportDeclaration(tokens: BoltTokenStream): BoltImportDeclaration {
+  public parseImportDirective(tokens: BoltTokenStream): BoltImportDirective {
+
+    let modifiers = 0;
+    if (tokens.peek().kind === SyntaxKind.BoltPubKeyword) {
+      tokens.get();
+      modifiers |= BoltModifiers.IsPublic;
+    }
 
     const t0 = tokens.get();
     assertToken(t0, SyntaxKind.BoltImportKeyword);
@@ -331,9 +340,12 @@ export class Parser {
     const filename = (t1 as BoltStringLiteral).value;
 
     const symbols: BoltImportSymbol[] = [];
+    const t2 = tokens.get();
+    if (t2.kind === SyntaxKind.BoltParenthesized) {
       // TODO implement grammar and parsing logic for symbols
+    }
 
-    const node = createBoltImportDeclaration(filename, symbols);
+    const node = createBoltImportDirective(modifiers, filename, symbols);
     setOrigNodeRange(node, t0, t1);
     return node;
   }
@@ -701,7 +713,7 @@ export class Parser {
     const t1 = tokens.peek();
     if (t1.kind === SyntaxKind.BoltMutKeyword) {
       tokens.get();
-      modifiers |= BoltDeclarationModifiers.Mutable;
+      modifiers |= BoltModifiers.Mutable;
     }
 
     const bindings = this.parsePattern(tokens)
@@ -821,7 +833,7 @@ export class Parser {
     let t0 = tokens.get();
     const firstToken = t0;
     if (t0.kind === SyntaxKind.BoltPubKeyword) {
-      modifiers |= BoltDeclarationModifiers.Public;
+      modifiers |= BoltModifiers.IsPublic;
       t0 = tokens.get();
     }
 
@@ -915,7 +927,7 @@ export class Parser {
     const firstToken = t0;
     if (t0.kind === SyntaxKind.BoltPubKeyword) {
       tokens.get();
-      modifiers |= BoltDeclarationModifiers.Public;
+      modifiers |= BoltModifiers.IsPublic;
       t0 = tokens.peek();
     }
 
@@ -946,7 +958,7 @@ export class Parser {
     const firstToken = t0;
 
     if (t0.kind === SyntaxKind.BoltPubKeyword) {
-      modifiers |= BoltDeclarationModifiers.Public;
+      modifiers |= BoltModifiers.IsPublic;
       t0 = tokens.get();
     }
 
@@ -985,13 +997,12 @@ export class Parser {
 
     if (k0.kind === SyntaxKind.BoltPubKeyword) {
       tokens.get();
-      modifiers |= BoltDeclarationModifiers.Public;
+      modifiers |= BoltModifiers.IsPublic;
       k0 = tokens.peek();
     }
 
     if (k0.kind === SyntaxKind.BoltForeignKeyword) {
       tokens.get();
-      modifiers |= BoltDeclarationModifiers.IsForeign;
       const l1 = tokens.get();
       if (l1.kind !== SyntaxKind.BoltStringLiteral) {
         throw new ParseError(l1, [SyntaxKind.BoltStringLiteral])
@@ -1150,7 +1161,7 @@ export class Parser {
     let t0 = tokens.get();
     const firstToken = t0;
     if (t0.kind === SyntaxKind.BoltPubKeyword) {
-      modifiers |= BoltDeclarationModifiers.Public;
+      modifiers |= BoltModifiers.IsPublic;
       t0 = tokens.get();
     }
     assertToken(t0, SyntaxKind.BoltTraitKeyword);
@@ -1181,7 +1192,7 @@ export class Parser {
     let t0 = tokens.get();
     const firstToken = t0;
     if (t0.kind === SyntaxKind.BoltPubKeyword) {
-      modifiers |= BoltDeclarationModifiers.Public;
+      modifiers |= BoltModifiers.IsPublic;
       t0 = tokens.get();
     }
     assertToken(t0, SyntaxKind.BoltImplKeyword);
@@ -1244,12 +1255,12 @@ export class Parser {
   }
 
   private getFirstTokenAfterModifiers(tokens: BoltTokenStream): BoltToken {
-    let mustBeDecl = false;
+    let mustBeDeclOrImport = false;
     let mustBeFunctionOrVariable = false;
     let i = 1;
     let t0 = tokens.peek(i);
     if (t0.kind === SyntaxKind.BoltPubKeyword) {
-      mustBeDecl = true;
+      mustBeDeclOrImport = true;
       t0 = tokens.peek(++i);
     }
     if (t0.kind === SyntaxKind.BoltForeignKeyword) {
@@ -1262,7 +1273,7 @@ export class Parser {
       && t0.kind !== SyntaxKind.BoltFnKeyword) {
       throw new ParseError(t0, [SyntaxKind.BoltStructKeyword, SyntaxKind.BoltFnKeyword]);
     }
-    if (mustBeDecl && KIND_DECLARATION_T0.indexOf(t0.kind) === -1) {
+    if (mustBeDeclOrImport && KIND_DECLARATION_T0.indexOf(t0.kind) === -1 && t0.kind !== SyntaxKind.BoltImportKeyword) {
       throw new ParseError(t0, KIND_DECLARATION_KEYWORD);
     }
     return t0;
@@ -1278,9 +1289,12 @@ export class Parser {
       return this.parseMacroCall(tokens);
     }
     const t0 = this.getFirstTokenAfterModifiers(tokens);
-    if (KIND_STATEMENT_T0.indexOf(t0.kind) !== -1) {
+    if (t0.kind ===  SyntaxKind.BoltImportKeyword) {
+      return this.parseImportDirective(tokens);
+    } else if (KIND_STATEMENT_T0.indexOf(t0.kind) !== -1) {
       return this.parseStatement(tokens);
     }
+    // FIXME This should only parse when the tokens are valid and otherwise display a friendly error message.
     return this.parseDeclaration(tokens);
   }
 
@@ -1372,12 +1386,13 @@ export class Parser {
   //  return lhs
   //}
 
-  public parseSourceFile(tokens: BoltTokenStream): BoltSourceFile {
+  public parseSourceFile(tokens: BoltTokenStream, pkg: Package): BoltSourceFile {
     const elements = this.parseSourceElements(tokens);
     const t1 = tokens.peek();
     assertToken(t1, SyntaxKind.EndOfFile);
     return createBoltSourceFile(
       elements,
+      pkg,
       new TextSpan(t1.span!.file, new TextPos(0,1,1), t1.span!.end.clone())
     );
   }
@@ -1518,12 +1533,12 @@ import * as fs from "fs"
 import {JSScanner} from "./foreign/js/scanner";
 import {emit} from "./emitter";
 
-export function parseSourceFile(filepath: string): BoltSourceFile {
+export function parseSourceFile(filepath: string, pkg: Package): BoltSourceFile {
   const file = new TextFile(filepath);
   const contents = fs.readFileSync(file.origPath, 'utf8');
   const scanner = new Scanner(file, contents)
   const parser = new Parser();
-  const sourceFile = parser.parseSourceFile(scanner);
+  const sourceFile = parser.parseSourceFile(scanner, pkg);
   setParents(sourceFile);
   return sourceFile;
 }

src/program.ts

@@ -1,4 +1,5 @@
 
+import { Package } from "./common"
 import { SourceFile } from "./ast"
 import { FastStringMap } from "./util";
 
@@ -7,12 +8,14 @@ export class Program {
   private transformed = new FastStringMap<string, SourceFile>();
 
   constructor(
-    sourceFiles: SourceFile[]
+    pkgs: Package[]
   ) {
-    for (const sourceFile of sourceFiles) {
+    for (const pkg of pkgs) {
+      for (const sourceFile of pkg.sourceFiles) {
         this.transformed.set(sourceFile.span!.file.fullPath, sourceFile);
       }
     }
+  }
 
   public getAllSourceFiles() {
     return this.transformed.values();

src/scanner.ts

@@ -9,6 +9,8 @@ import {
 
 import {
   BoltToken,
+  createBoltImportKeyword,
+  createBoltExportKeyword,
   createBoltRArrowAlt,
   createEndOfFile,
   createBoltIdentifier,
@@ -308,6 +310,8 @@ export class Scanner {
           case 'trait':   return createBoltTraitKeyword(span);
           case 'impl':    return createBoltImplKeyword(span);
           case 'type':    return createBoltTypeKeyword(span);
+          //case 'export':  return createBoltExportKeyword(span);
+          case 'import':  return createBoltImportKeyword(span);
           case 'foreign': return createBoltForeignKeyword(span);
           case 'let':     return createBoltLetKeyword(span);
           case 'mut':     return createBoltMutKeyword(span);

src/treegen/ast-template.js

@@ -58,6 +58,8 @@ function isSyntax(value) {
       && value.__NODE_TYPE !== undefined;
 }
 
+exported.isSyntax = isSyntax;
+
 let nextNodeId = 1;
 
 function createNode(nodeType) {

src/treegen/index.ts

@@ -4,6 +4,8 @@ import * as path from "path"
 
 const PACKAGE_ROOT = path.resolve(__dirname, '..', '..');
 
+const CUSTOM_TYPES = ['Package'];
+
 import { Syntax, Declaration, NodeDeclaration, TypeDeclaration, EnumDeclaration, TypeNode, NodeField } from "./ast"
 import { MapLike } from "../util"
 import { FileWriter } from "./util"
@@ -96,6 +98,13 @@ export function generateAST(decls: Declaration[]) {
 
   // Write corresponding TypeScript declarations
 
+
+  // FIXME These imports are specific to our project and should somehow
+  //       form part of the user specification.
+  dtsFile.write('\nimport { Package } from "./common"\n\n');
+
+  dtsFile.write('export function isSyntax(value: any): value is Syntax;\n\n');
+
   dtsFile.write(`\nexport const enum SyntaxKind {\n`);
   for (const decl of leafNodes) {
     dtsFile.write(`  ${decl.name} = ${decl.index},\n`);
@@ -111,6 +120,7 @@ export function setParents(node: Syntax): void;
 export type SyntaxRange = [Syntax, Syntax];
 
 interface SyntaxBase<K extends SyntaxKind> {
+  id: number;
   kind: K;
   parentNode: ParentTypesOf<K> | null;
   span: TextSpan | null;
@@ -227,6 +237,8 @@ export type ResolveSyntaxKind<K extends SyntaxKind> = Extract<Syntax, { kind: K
         return `${emitTypeScriptType(typeNode.typeArgs[0])} | null`;
       } else if (typeNode.name === 'Vec') {
         return `${emitTypeScriptType(typeNode.typeArgs[0])}[]`;
+      } else if (CUSTOM_TYPES.indexOf(typeNode.name) !== -1) {
+        return typeNode.name;
       } else if (typeNode.name === 'String') {
         return `string`;
       } else if (typeNode.name === 'Int') {

src/util.ts

@@ -14,6 +14,14 @@ export interface JsonArray extends Array<Json> {  };
 export interface JsonObject { [key: string]: Json }
 export type Json = null | string | boolean | number | JsonArray | JsonObject;
 
+export function isString(value: any): boolean {
+  return typeof value === 'string';
+}
+
+export function hasOwnProperty<T extends object, K extends PropertyKey>(obj: T, key: K): boolean {
+  return Object.prototype.hasOwnProperty.call(obj, key);
+}
+
 export function uniq<T>(elements: T[]): T[] {
   const out: T[] = [];
   const visited = new Set<T>();