parsed type params

ascandone · Jan 22, 2024 · 29b9e59 · 29b9e59
1 parent 3b166ba
commit 29b9e59
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Showing 5 changed files with 64 additions and 1 deletion.
diff --git a/src/__snapshots__/parser.test.ts.snap b/src/__snapshots__/parser.test.ts.snap
@@ -1259,12 +1259,47 @@ exports[`parse let block with two let stmts 1`] = `
 }
 `;
 
+exports[`type declarations > many type params 1`] = `
+{
+  "declarations": [],
+  "typeDeclarations": [
+    {
+      "name": "T",
+      "params": [
+        "a",
+        "b",
+        "c",
+      ],
+      "type": "adt",
+      "variants": [],
+    },
+  ],
+}
+`;
+
+exports[`type declarations > single type param 1`] = `
+{
+  "declarations": [],
+  "typeDeclarations": [
+    {
+      "name": "T",
+      "params": [
+        "a",
+      ],
+      "type": "adt",
+      "variants": [],
+    },
+  ],
+}
+`;
+
 exports[`type declarations > trailing comma after variants 1`] = `
 {
   "declarations": [],
   "typeDeclarations": [
     {
       "name": "T",
+      "params": [],
       "type": "adt",
       "variants": [
         {
@@ -1287,6 +1322,7 @@ exports[`type declarations > type with a variant with complex args 1`] = `
   "typeDeclarations": [
     {
       "name": "T",
+      "params": [],
       "type": "adt",
       "variants": [
         {
@@ -1327,6 +1363,7 @@ exports[`type declarations > type with a variant with no args 1`] = `
   "typeDeclarations": [
     {
       "name": "T",
+      "params": [],
       "type": "adt",
       "variants": [
         {
@@ -1345,6 +1382,7 @@ exports[`type declarations > type with a variant with no args 2`] = `
   "typeDeclarations": [
     {
       "name": "T",
+      "params": [],
       "type": "adt",
       "variants": [
         {
@@ -1369,6 +1407,7 @@ exports[`type declarations > type with many variants 1`] = `
   "typeDeclarations": [
     {
       "name": "T",
+      "params": [],
       "type": "adt",
       "variants": [
         {
@@ -1391,6 +1430,7 @@ exports[`type declarations > type with no variants 1`] = `
   "typeDeclarations": [
     {
       "name": "Never",
+      "params": [],
       "type": "adt",
       "variants": [],
     },

diff --git a/src/ast.ts b/src/ast.ts
@@ -64,6 +64,7 @@ export type Declaration<TypeMeta = {}> = TypeMeta & {
 export type TypeVariant = { name: string; args: TypeAst[] };
 export type TypeDeclaration = {
   type: "adt";
+  params: string[];
   name: string;
   variants: TypeVariant[];
 };

diff --git a/src/parser.test.ts b/src/parser.test.ts
@@ -282,6 +282,16 @@ describe("type declarations", () => {
     const src = `type T { A, B, }`;
     expect(unsafeParse(src)).toMatchSnapshot();
   });
+
+  test("single type param", () => {
+    const src = `type T<a> { }`;
+    expect(unsafeParse(src)).toMatchSnapshot();
+  });
+
+  test("many type params", () => {
+    const src = `type T<a, b, c> { }`;
+    expect(unsafeParse(src)).toMatchSnapshot();
+  });
 });
 
 function spanOf(src: string, substr: string = src): Span {

diff --git a/src/parser.ts b/src/parser.ts
@@ -191,6 +191,9 @@ semantics.addOperation<Statement>("statement()", {
   TypeDeclaration_typeDef(
     _type,
     typeName,
+    _lT,
+    params,
+    _rT,
     _lbracket,
     variants,
     _trailingComma,
@@ -200,10 +203,19 @@ semantics.addOperation<Statement>("statement()", {
       .asIteration()
       .children.map<TypeVariant>((n) => n.typeVariant());
 
+    let params_: string[] = [];
+    if (params.numChildren > 0) {
+      params_ = params
+        .child(0)
+        .asIteration()
+        .children.map((c) => c.sourceString);
+    }
+
     return {
       type: "typeDeclaration",
       decl: {
         type: "adt",
+        params: params_,
         name: typeName.sourceString,
         variants: variants_,
       },

diff --git a/src/parser/grammar.ohm b/src/parser/grammar.ohm
@@ -7,7 +7,7 @@ Program {
     = "let" ident (":" Type)? "=" Exp  -- letStmt
 
   TypeDeclaration
-    = "type" typeName "{" ListOf<TypeVariant, ","> ","? "}" -- typeDef
+    = "type" typeName ("<" NonemptyListOf<typeVar, ","> ">")? "{" ListOf<TypeVariant, ","> ","? "}" -- typeDef
 
   // --- Expressions