initial commit

betarules.rules

@@ -0,0 +1,5 @@
+term := Var | "\\" Var "." term @ label="abstraction" | term " " term @ label="application" | "(" term ")" @ hidden=True
+simple_type := Var | simple_type "->" simple_type @ label="arrow"
+
+assoc "application" left
+assoc "arrow" right

lambda.lark

@@ -0,0 +1,8 @@
+start: term
+abstraction: "\\" VARIABLE "." term
+application: term " " term
+term: abstraction | application | VARIABLE | "(" term ")"
+
+VARIABLE: LETTER+
+
+%import common.LETTER

parsetest.py

@@ -0,0 +1,11 @@
+from lark import Lark
+
+
+with open("termdef.lark") as parse_file:
+    parser = Lark(parse_file)
+
+with open("betarules.rules") as b:
+    rules_text = "\n".join(b.readlines())
+
+print(parser.parse(rules_text).pretty())
+

termdef.lark

@@ -0,0 +1,19 @@
+start: rule+
+rule: ntermdef | assocdef
+ntermdef: IDENTIFIER ":=" rhs ("|" rhs)*
+rhs: token+ ("@" annotation+)?
+token: STRING | IDENTIFIER
+annotation: IDENTIFIER "=" value
+assocdef: "assoc" STRING lr
+lr:  LEFT | RIGHT
+LEFT: "left"
+RIGHT: "right"
+WORD: ("a".."z" | "0".."9")+
+
+value: STRING | SIGNED_NUMBER | "True" | "False"
+
+%import common.WS
+%import common.SIGNED_NUMBER
+%ignore WS
+%import common.ESCAPED_STRING   -> STRING
+%import common.CNAME   -> IDENTIFIER