Add defn, alias for define

Author: WyattBlue

auto_editor/lang/stdenv.py

@@ -962,6 +962,7 @@ def change_file_ext(a: str, ext: str) -> str:
         # syntax
         "lambda": Syntax(syn_lambda),
         "λ": Syntax(syn_lambda),
+        "defn": Syntax(syn_define),
         "define": Syntax(syn_define),
         "define/c": Syntax(syn_definec),
         "set!": Syntax(syn_set),

docs/doc.pal

@@ -177,6 +177,7 @@
 (define core-docs {hash
     "Assignment" #[
         (syntax "define" "id expr" (text "Set "'id" to the result of "'expr"."))
+        (syntax "defn" "id expr" (text "Alias for "'define"."))
         (syntax "set!" "id expr"
             (text
                 "Set "'id" to the result of "'expr" if "'id