Improve handling of immediate args, especially re stdlib functions

tealish/base.py

@@ -158,6 +158,9 @@ def lookup_const(self, name: str) -> Tuple["TealishType", ConstValue]:
     def lookup_avm_constant(self, name: str) -> Tuple["TealishType", Any]:
         return lang_spec.lookup_avm_constant(name)
 
+    def lookup_op_field(self, op_name: str, field_name: str) -> "TealishType":
+        return lang_spec.lookup_op_field(op_name, field_name)
+
     # TODO: these attributes are only available on Node and other children types
     # we should either define them here or something else?
     @property

tealish/expression_nodes.py

@@ -112,7 +112,11 @@ def process(self) -> None:
             # builtin TEAL constants
             type, value = self.lookup_avm_constant(self.name)
         except KeyError:
-            raise CompileError(f'Unknown builtin enum "{self.name}"', node=self)
+            try:
+                # op field
+                type = self.lookup_op_field(self.parent.name, self.name)
+            except KeyError:
+                raise CompileError(f'Unknown builtin enum "{self.name}"', node=self)
         if not isinstance(type, (IntType, BytesType, BigIntType, AddrType)):
             raise CompileError(f"Unexpected const type {type}", node=self)
 

tealish/langspec.py

@@ -237,6 +237,11 @@ def lookup_op(self, name: str) -> Op:
             raise KeyError(f'Op "{name}" does not exist!')
         return self.ops[name]
 
+    def lookup_op_field(self, op_name: str, field_name: str) -> Op:
+        op = self.lookup_op(op_name)
+        type = op.arg_enum_dict[field_name]
+        return type
+
     def lookup_avm_constant(self, name: str) -> Tuple[TealishType, Any]:
         if name not in constants:
             raise KeyError(f'Constant "{name}" does not exist!')