Utilities

Sexpr is a utility wrapper class for s-expressions. It provides some convienience properties, such as tag, body and in-place versions of inject and extend. Sexpr subclasses list.

sexp = grammar.sexpr(['and', ['literal', True], ['literal', False]])
# or Sexpr(<expression>, grammar)

sexpr.tag
# = 'and'

sexpr.body
# = ['literal', True], ['literal', False']

sexp.inject(lambda exp: ['not', exp])
# = ['not', ['and', ['literal', True], ['literal', False]]]