Ignore whitespace with PEG.js

Question

I want to ignore whitespaces and new lines with my grammar so they are missing in the PEG.js output. Also, a literal within brackets should be returned in a ne

Answer 1

You have to break up the grammar more, using more "non-terminals" (not sure if that's what you call them in a PEG):

start
  = article animal stmt_list

article
  = article:'a'? __ { return article; }

animal
  = animal:('cat'/'dog') _ { return animal; }

stmt_list
  = '(' _ exp:[a-zA-Z]+ _ ')' { return [ exp.join('') ]; }

// optional whitespace
_  = [ \t\r\n]*

// mandatory whitespace
__ = [ \t\r\n]+

Thanks for asking this question!

Edit: To increase readability, have two productions: _ and __