Anyone out there use simpleparse? If so, I have a problem that I can't
seem to solve...I need to be able to parse this line:
"""Cen2 = Cen(OUT, "Cep", "ies", wh, 544, (wh/ht));"""
with this grammar:
grammar = r'''
declaration := ws, line, (ws, line)*, ws
line := (statement / assignment), ';', ws
assignment := identifier, ws, '=', ws, statement
statement := identifier, '(', arglist?, ')', chars?
identifier := ([a-zA-Z0-9_.:])+
arglist := arg, (',', ws, arg)*
arg := expr/ statement / identifier / num / str /
curve / spline / union / conditional / definition
definition := typedef?, ws, identifier, ws, '=', ws, arg
typedef := ([a-zA-Z0-9_])+
expr := termlist, ( operator, termlist )+
termlist := ( '(', expr, ')' ) / term
term := call / identifier / num
call := identifier, '(', arglist?, ')'
union := '{{', ws, (arg, ws, ';', ws)*, arg, ws, '}}'
operator := ( '+' / '-' / '/' / '*' /
'==' / '>=' / '<=' / '>' / '<' )
conditional := termlist, ws, '?', ws, termlist, ws, ':', ws, termlist
curve := (list / num), '@', num
spline := (cv, ',')*, cv
cv := identifier, '@', num
list := '[', arg, (',', ws, arg)*, ']'
str := '"', ([;] / chars)*, '"'
num := ( scinot / float / int )
<chars> := ('-' / '/' / '?' / [EMAIL PROTECTED]&\*\+=<> :])+
<int> := ([-+]?, [0-9]+)
<float> := ([-+]?, [0-9\.]+)
<scinot> := (float, 'e', int)
<ws> := [ \t\n]*
'''
But it fails. The problem is with how arglist/arg/expr are defined,
which makes it unable to handle the parenthesized expression at the end
of the line:
(wh/ht)
But everything I've tried to correct that problem fails. In the end, it
needs to be able to parse that line with those parentheses around wh/ht,
or without them.
Recursive parsing of expressions just seems hard to do in simpleparse,
and is beyond my parsing knowledge.
Here's the code to get the parser going:
from simpleparse.parser import Parser
p = Parser(grammar, 'line')
import pprint
bad_line = """Cen2 = Cen(OUT, "Cep", "ies", wh, 544, (wh/ht));"""
pprint.pprint(p.parse(bad_line))
Any help greatly appreciated, thanks,
-Dave
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