Analyze functions in two passes (signatures, then bodies) to allow for forward use

trans/transpiler/phases/typing/block.py

@@ -38,8 +38,7 @@ class ScoperBlockVisitor(ScoperVisitor):
             self.scope.vars[alias.asname or alias.name] = VarDecl(VarKind.LOCAL, thing)
 
     def visit_Module(self, node: ast.Module):
-        for stmt in node.body:
-            self.visit(stmt)
+        self.visit_block(node.body)
 
     def get_type(self, node: ast.expr) -> BaseType:
         if type := getattr(node, "type", None):
@@ -98,13 +97,7 @@ class ScoperBlockVisitor(ScoperVisitor):
         ftype.optional_at = 1 + len(node.args.args) - len(node.args.defaults)
         for arg, ty in zip(node.args.args, argtypes):
             scope.vars[arg.arg] = VarDecl(VarKind.LOCAL, ty)
-        for b in node.body:
-            decls = {}
-            visitor = ScoperBlockVisitor(scope, decls)
-            visitor.visit(b)
-            b.decls = decls
-        if not scope.has_return:
-            rtype.return_type.unify(TY_NONE)
+        self.fdecls.append((node, rtype.return_type))
 
     def visit_ClassDef(self, node: ast.ClassDef):
         ctype = UserType(node.name)
@@ -115,8 +108,7 @@ class ScoperBlockVisitor(ScoperVisitor):
         node.inner_scope = scope
         node.type = ctype
         visitor = ScoperClassVisitor(scope)
-        for b in node.body:
-            visitor.visit(b)
+        visitor.visit_block(node.body)
 
     def visit_If(self, node: ast.If):
         scope = self.scope.child(ScopeKind.FUNCTION_INNER)
@@ -124,13 +116,11 @@ class ScoperBlockVisitor(ScoperVisitor):
         self.expr().visit(node.test)
         then_scope = scope.child(ScopeKind.FUNCTION_INNER)
         then_visitor = ScoperBlockVisitor(then_scope, self.root_decls)
-        for b in node.body:
-            then_visitor.visit(b)
+        then_visitor.visit_block(node.body)
         if node.orelse:
             else_scope = scope.child(ScopeKind.FUNCTION_INNER)
             else_visitor = ScoperBlockVisitor(else_scope, self.root_decls)
-            for b in node.orelse:
-                else_visitor.visit(b)
+            else_visitor.visit_block(node.orelse.body)
 
     def visit_While(self, node: ast.While):
         scope = self.scope.child(ScopeKind.FUNCTION_INNER)
@@ -138,8 +128,7 @@ class ScoperBlockVisitor(ScoperVisitor):
         self.expr().visit(node.test)
         body_scope = scope.child(ScopeKind.FUNCTION_INNER)
         body_visitor = ScoperBlockVisitor(body_scope, self.root_decls)
-        for b in node.body:
-            body_visitor.visit(b)
+        body_visitor.visit_block(node.body)
         if node.orelse:
             raise NotImplementedError(node.orelse)
 
@@ -151,8 +140,7 @@ class ScoperBlockVisitor(ScoperVisitor):
         self.expr().visit(node.iter)
         body_scope = scope.child(ScopeKind.FUNCTION_INNER)
         body_visitor = ScoperBlockVisitor(body_scope, self.root_decls)
-        for b in node.body:
-            body_visitor.visit(b)
+        body_visitor.visit_block(node.body)
         if node.orelse:
             raise NotImplementedError(node.orelse)
 
@@ -183,6 +171,8 @@ class ScoperBlockVisitor(ScoperVisitor):
         if isinstance(node, ast.AST):
             super().visit(node)
             node.scope = self.scope
+        else:
+            raise NotImplementedError(node)
 
     def visit_Break(self, node: ast.Break):
         pass  # TODO: check in loop

trans/transpiler/phases/typing/class_.py

 # coding: utf-8
 import ast
-from dataclasses import dataclass
+from dataclasses import dataclass, field
 
 from transpiler.phases.typing import FunctionType, ScopeKind, VarDecl, VarKind, TY_NONE
 from transpiler.phases.typing.common import ScoperVisitor
+from transpiler.phases.typing.types import PromiseKind, Promise, BaseType
 
 
 @dataclass
 class ScoperClassVisitor(ScoperVisitor):
+    fdecls: list[(ast.FunctionDef, BaseType)] = field(default_factory=list)
+
     def visit_AnnAssign(self, node: ast.AnnAssign):
         assert node.value is None, "Class field should not have a value"
         assert node.simple == 1, "Class field should be simple (identifier, not parenthesized)"
@@ -20,6 +23,9 @@ class ScoperClassVisitor(ScoperVisitor):
         argtypes = [self.visit_annotation(arg.annotation) for arg in node.args.args]
         argtypes[0].unify(self.scope.obj_type)  # self parameter
         rtype = self.visit_annotation(node.returns)
+        inner_rtype = rtype
+        if node.name != "__init__":
+            rtype = Promise(rtype, PromiseKind.TASK)
         ftype = FunctionType(argtypes, rtype)
         self.scope.obj_type.methods[node.name] = ftype
         scope = self.scope.child(ScopeKind.FUNCTION)
@@ -29,10 +35,4 @@ class ScoperClassVisitor(ScoperVisitor):
         node.type = ftype
         for arg, ty in zip(node.args.args, argtypes):
             scope.vars[arg.arg] = VarDecl(VarKind.LOCAL, ty)
-        for b in node.body:
-            decls = {}
-            visitor = ScoperBlockVisitor(scope, decls)
-            visitor.visit(b)
-            b.decls = decls
-        if not scope.has_return:
-            rtype.unify(TY_NONE)
+        self.fdecls.append((node, inner_rtype))

trans/transpiler/phases/typing/common.py

@@ -4,7 +4,7 @@ from typing import Dict, Optional
 
 from transpiler.phases.typing.annotations import TypeAnnotationVisitor
 from transpiler.phases.typing.scope import Scope, ScopeKind, VarDecl
-from transpiler.phases.typing.types import BaseType, TypeVariable
+from transpiler.phases.typing.types import BaseType, TypeVariable, TY_NONE
 from transpiler.phases.utils import NodeVisitorSeq
 
 PRELUDE = Scope.make_global()
@@ -18,4 +18,18 @@ class ScoperVisitor(NodeVisitorSeq):
         return TypeAnnotationVisitor(self.scope)
 
     def visit_annotation(self, expr: Optional[ast.expr]) -> BaseType:
-        return self.anno().visit(expr) if expr else TypeVariable()
\ No newline at end of file
+        return self.anno().visit(expr) if expr else TypeVariable()
+
+    def visit_block(self, block: list[ast.AST]):
+        from transpiler.phases.typing.block import ScoperBlockVisitor
+        self.fdecls = []
+        for b in block:
+            self.visit(b)
+        for node, rtype in self.fdecls:
+            for b in node.body:
+                decls = {}
+                visitor = ScoperBlockVisitor(node.inner_scope, decls)
+                visitor.visit(b)
+                b.decls = decls
+            if not node.inner_scope.has_return:
+                rtype.unify(TY_NONE)
\ No newline at end of file