parsing type args params

ascandone · Jan 19, 2024 · 397741d · 397741d
1 parent adc68dd
commit 397741d
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Showing 4 changed files with 119 additions and 3 deletions.
diff --git a/src/__snapshots__/parser.test.ts.snap b/src/__snapshots__/parser.test.ts.snap
@@ -1300,6 +1300,105 @@ exports[`parses a concrete type with no args as a type hint 1`] = `
 }
 `;
 
+exports[`parses concrete type with 1 arg 1`] = `
+{
+  "statements": [
+    {
+      "binding": {
+        "name": "x",
+        "span": [
+          4,
+          5,
+        ],
+      },
+      "span": [
+        0,
+        22,
+      ],
+      "type": "let",
+      "typeHint": {
+        "args": [
+          {
+            "args": [],
+            "name": "Int",
+            "type": "named",
+          },
+        ],
+        "name": "Maybe",
+        "span": [
+          8,
+          18,
+        ],
+        "type": "named",
+      },
+      "value": {
+        "span": [
+          21,
+          22,
+        ],
+        "type": "constant",
+        "value": {
+          "type": "int",
+          "value": 0,
+        },
+      },
+    },
+  ],
+}
+`;
+
+exports[`parses concrete type with 2 args 1`] = `
+{
+  "statements": [
+    {
+      "binding": {
+        "name": "x",
+        "span": [
+          4,
+          5,
+        ],
+      },
+      "span": [
+        0,
+        29,
+      ],
+      "type": "let",
+      "typeHint": {
+        "args": [
+          {
+            "args": [],
+            "name": "Int",
+            "type": "named",
+          },
+          {
+            "args": [],
+            "name": "Bool",
+            "type": "named",
+          },
+        ],
+        "name": "Result",
+        "span": [
+          8,
+          25,
+        ],
+        "type": "named",
+      },
+      "value": {
+        "span": [
+          28,
+          29,
+        ],
+        "type": "constant",
+        "value": {
+          "type": "int",
+          "value": 0,
+        },
+      },
+    },
+  ],
+}
+`;
+
 exports[`parses underscore type 1`] = `
 {
   "statements": [

diff --git a/src/parser.test.ts b/src/parser.test.ts
@@ -222,6 +222,16 @@ test("parses underscore type", () => {
   expect(unsafeParse(src)).toMatchSnapshot();
 });
 
+test("parses concrete type with 1 arg", () => {
+  const src = "let x : Maybe<Int> = 0";
+  expect(unsafeParse(src)).toMatchSnapshot();
+});
+
+test("parses concrete type with 2 args", () => {
+  const src = "let x : Result<Int, Bool> = 0";
+  expect(unsafeParse(src)).toMatchSnapshot();
+});
+
 function spanOf(src: string, substr: string = src): Span {
   const index = src.indexOf(substr);
   return [index, index + substr.length];

diff --git a/src/parser.ts b/src/parser.ts
@@ -142,10 +142,17 @@ semantics.addOperation<TypeHint>("typeHint()", {
     return { type: "any" };
   },
 
-  TypeHint_named(ident) {
+  TypeHint_named(ident, _lbracket, args, _rbracket) {
+    let args_: TypeHint[] = [];
+    if (args.numChildren > 0) {
+      args_ = args
+        .child(0)
+        .asIteration()
+        .children.map((c) => c.typeHint());
+    }
     return {
       type: "named",
-      args: [],
+      args: args_,
       name: ident.sourceString,
     };
   },

diff --git a/src/parser/grammar.ohm b/src/parser/grammar.ohm
@@ -78,7 +78,7 @@ Program {
   // --- Types
 
   TypeHint
-    = typeIdent  -- named
+    = typeIdent ("<" ListOf<TypeHint, ","> ">")?  -- named
     | "_" -- any
 
   typeIdent  (an identifier)