feature: parser catch and dot

graeme-lockley · May 19, 2024 · de88706 · de88706
1 parent 98c9ac4
commit de88706
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Showing 3 changed files with 115 additions and 10 deletions.
diff --git a/docs/parser.md b/docs/parser.md
@@ -95,3 +95,35 @@ Now that we have the basic mechanism in place, let's systematically go through t
   ]
 }
 ```
+
+## Catch
+
+```rebo-repl
+> rebo.lang.parse("10 catch e -> e")
+{ kind: "exprs"
+, value: 
+  [ { kind: "catche"
+    , value: { kind: "literalInt", value: 10 }
+    , cases:
+      [ { pattern: { kind: "identifier", value: "e" }
+        , body: { kind: "identifier", value: "e" }
+        }
+      ]
+    }
+  ]
+}
+```
+
+## Dot
+
+```rebo-repl
+> rebo.lang.parse("a.b")
+{ kind: "exprs"
+, value: 
+  [ { kind: "dot"
+    , record: { kind: "identifier", value: "a" }
+    , field: "b"
+    }
+  ]
+}
+```
diff --git a/src/ast.zig b/src/ast.zig
@@ -133,16 +133,6 @@ pub const CallExpression = struct {
     args: []*Expression,
 };
 
-pub const IdDeclarationExpression = struct {
-    name: *SP.String,
-    value: *Expression,
-
-    pub fn deinit(self: *IdDeclarationExpression, allocator: std.mem.Allocator) void {
-        self.name.decRef();
-        destroyExpr(allocator, self.value);
-    }
-};
-
 pub const CatchExpression = struct {
     value: *Expression,
     cases: []MatchCase,
@@ -158,6 +148,16 @@ pub const DotExpression = struct {
     }
 };
 
+pub const IdDeclarationExpression = struct {
+    name: *SP.String,
+    value: *Expression,
+
+    pub fn deinit(self: *IdDeclarationExpression, allocator: std.mem.Allocator) void {
+        self.name.decRef();
+        destroyExpr(allocator, self.value);
+    }
+};
+
 pub const IfCouple = struct {
     condition: ?*Expression,
     then: *Expression,

diff --git a/src/builtins/parser.zig b/src/builtins/parser.zig
@@ -72,6 +72,49 @@ fn emit(machine: *Helper.Runtime, ast: *AST.Expression, position: bool) !void {
             }
             try machine.setRecordItemBang(pos);
         },
+        .catche => {
+            try machine.pushEmptyRecordValue();
+
+            try machine.pushStringValue("kind");
+            try machine.pushStringValue("catche");
+            try machine.setRecordItemBang(pos);
+
+            try machine.pushStringValue("value");
+            try emit(machine, ast.kind.catche.value, position);
+            try machine.setRecordItemBang(pos);
+
+            try machine.pushStringValue("cases");
+            try machine.pushEmptySequenceValue();
+            for (ast.kind.catche.cases) |case| {
+                try machine.pushEmptyRecordValue();
+
+                try machine.pushStringValue("pattern");
+                try emitPattern(machine, case.pattern, position);
+                try machine.setRecordItemBang(pos);
+
+                try machine.pushStringValue("body");
+                try emit(machine, case.body, position);
+                try machine.setRecordItemBang(pos);
+
+                try machine.appendSequenceItemBang(pos);
+            }
+            try machine.setRecordItemBang(pos);
+        },
+        .dot => {
+            try machine.pushEmptyRecordValue();
+
+            try machine.pushStringValue("kind");
+            try machine.pushStringValue("dot");
+            try machine.setRecordItemBang(pos);
+
+            try machine.pushStringValue("record");
+            try emit(machine, ast.kind.dot.record, position);
+            try machine.setRecordItemBang(pos);
+
+            try machine.pushStringValue("field");
+            try machine.pushStringValue(ast.kind.dot.field.slice());
+            try machine.setRecordItemBang(pos);
+        },
         .exprs => {
             try machine.pushEmptyRecordValue();
 
@@ -125,3 +168,33 @@ fn emit(machine: *Helper.Runtime, ast: *AST.Expression, position: bool) !void {
         try machine.setRecordItemBang(pos);
     }
 }
+
+fn emitPattern(machine: *Helper.Runtime, ast: *AST.Pattern, position: bool) !void {
+    switch (ast.kind) {
+        .identifier => {
+            try machine.pushEmptyRecordValue();
+
+            try machine.pushStringValue("kind");
+            try machine.pushStringValue("identifier");
+            try machine.setRecordItemBang(pos);
+
+            try machine.pushStringValue("value");
+            try machine.pushStringValue(ast.kind.identifier.slice());
+            try machine.setRecordItemBang(pos);
+        },
+        else => {
+            std.io.getStdErr().writer().print("unreachable: {}\n", .{ast.kind}) catch {};
+            unreachable;
+        },
+    }
+
+    if (position) {
+        try machine.pushStringValue("position");
+        try machine.pushEmptySequenceValue();
+        try machine.pushIntValue(@intCast(ast.position.start));
+        try machine.appendSequenceItemBang(pos);
+        try machine.pushIntValue(@intCast(ast.position.end));
+        try machine.appendSequenceItemBang(pos);
+        try machine.setRecordItemBang(pos);
+    }
+}