-function thenDo(m : Maybe<TokenPair>, f : Function){
- if (m._tag == "None"){
- return m;
- }else{
- var a : Maybe<TokenPair> = f(m.value);
- if (a._tag == "Some"){
- a.value.ast = m.value.ast.concat(a.value.ast);
- }
+const lexer = p.buildLexer([
+ [true, /^\d+(\.\d+)?/g, TokenKind.Number],
+ [true, /^\;/g, TokenKind.Semicolon],
+ [true, /^[-][-][-]/g, TokenKind.Seperator],
+ [true, /^[\+\-\*\/\&\|\!\^\<\>\~\=\?]+/g, TokenKind.Op],
+ [true, /^\@+/g, TokenKind.ExprMark],
+ [true, /^[()\[\]{}]/g, TokenKind.Paren],
+ [true, /^["]([\"]|[\\].)*["]/g, TokenKind.Str],
+ [true, /^[']([\']|[\\].)*[']/g, TokenKind.Str],
+ [true, /^[()\[\]{}]/g, TokenKind.Paren],
+ [true, /^[^\s\n\t\r;]+/g, TokenKind.Id],
+ [false, /^(\s|\n|\r|\t)+/g, TokenKind.SpaceNL]
+]);