gistfile1.txt

%{
[@@@warning "-39"]
%}
%start <unit> file

%%

file:
  | MODULE UIDENT item* EOF {}

item:
  | DEF LIDENT EQ exp {}

stmt:
  | exp SEMICOLON {}
  | LIDENT EQ exp SEMICOLON {}
  | IF exp THEN stmt {}
  | IF exp LBRACE stmt+ RBRACE {}
  | IF exp LBRACE stmt+ RBRACE ELSE LBRACE stmt+ RBRACE {}
  | FOR LBRACE stmt+ RBRACE {}
  | FOR exp LBRACE stmt+ RBRACE {}
  | WHILE exp DO stmt {}
  | WHILE exp LBRACE stmt+ RBRACE {}
  | DO stmt WHILE exp SEMICOLON {}
  | DO LBRACE stmt+ RBRACE WHILE exp SEMICOLON {}
  | RETURN exp SEMICOLON {}
  | RETURN UIDENT EQ exp SEMICOLON {}

seq_exp:
  | exp {}
  | stmt seq_exp {}

exp:
  | ident_prefix_exp {}

ident_prefix_exp:
  | ident_infix_exp {}
  | LIDENT ident_prefix_exp {}
  | IF exp THEN exp ELSE exp {}
  | IF exp LBRACE seq_exp RBRACE ELSE LBRACE seq_exp RBRACE {}
  | LIDENT EQ_GT exp {}
  | FUNC LPAREN list_allow_trailing_separator(COMMA, param) RPAREN EQ_GT exp {}

ident_infix_exp:
  | infix_exp {}
  | infix_exp LIDENT ident_infix_exp {}

infix_exp:
  | prefix_exp {}
  | prefix_exp infix_op infix_exp {}

%inline infix_op:
  | PLUS {}
  | MINUS {}
  | STAR {}
  | SLASH {}
  | LT {}
  | LT_EQ {}
  | GT {}
  | GT_EQ {}
  | EQ_EQ {}
  | BANG_EQ {}

prefix_exp:
  | prefix_op postfix_exp {}

%inline prefix_op:
  | MINUS {}

postfix_exp:
  | atom_exp {}
  | LIDENT_LPAREN list_allow_trailing_separator(COMMA, arg) RPAREN {}
  | postfix_exp LPAREN list_allow_trailing_separator(COMMA, arg) RPAREN {}
  | postfix_exp LBRACKET exp RBRACKET {}
  | postfix_exp DOT_LIDENT {}

arg:
  | LIDENT_COLON exp {}
  | exp {}

atom_exp:
  | HALT {}
  | INT {}
  | FLOAT {}
  | LIDENT {}
  | UIDENT {}
  | LPAREN exp RPAREN {}
  | BLOCK LBRACE seq_exp RBRACE {}
  | BLOCK UIDENT LBRACE seq_exp RBRACE {}
  | FUNC LPAREN list_allow_trailing_separator(COMMA, param) RPAREN LBRACE seq_exp RBRACE {}

param:
  | LIDENT_COLON LIDENT {}
  | LIDENT {}

list_allow_trailing_separator(SEP, X):
  | { [] }
  | x=X { [x] }
  | x=X SEP l=list_allow_trailing_separator(SEP, X) { x :: l }