if with no else

1 files changed, 10 insertions, 9 deletions

diff --git a/std.py b/std.py
index 0b39d44..fe0ede1 100644
--- a/std.py
+++ b/std.py
@@ -59,18 +59,18 @@ def std_concat(arg1, arg2):
     return NebString(f"{arg1.value}{arg2.value}")
 
 # flow control
-def std_if(cond, t_branch, f_branch):
+def std_if(cond, t_branch, f_branch=None):
     if cond.value:
         if isinstance(t_branch, NebExpression):
-            ret = evaluate_expression(t_branch)
+            return evaluate_expression(t_branch)
         else:
-            ret = t_branch
-    else:
+            return t_branch
+    elif f_branch is not None:
         if isinstance(t_branch, NebExpression):
-            ret = evaluate_expression(f_branch)
+            return evaluate_expression(f_branch)
         else:
-            ret = f_branch
-    return ret
+            return f_branch
+    return NebBool(True)
 
 # type validation
 def std_is_string(arg):
@@ -159,8 +159,9 @@ def build_std():
     STD["concat"] = [concat_string_string]
 
     # flow control
-    if_bool_expr_expr = FuncImpl(NebFunction("if", [NebBool, NebAny, NebAny], NebAny), std_if)
-    STD["if"] = [if_bool_expr_expr]
+    if_bool_any_any = FuncImpl(NebFunction("if", [NebBool, NebAny, NebAny], NebAny), std_if)
+    if_bool_any = FuncImpl(NebFunction("if", [NebBool, NebAny], NebAny), std_if)
+    STD["if"] = [if_bool_any_any, if_bool_any]
 
     # type checking
     is_string = FuncImpl(NebFunction("string?", [NebAny], NebBool), std_is_string)