Re: [Pyparsing] setResultsName: request for clarification

[Eike W. <eik...@gm...>]

On Thursday 01 May 2008 17:54, stefaan.himpe wrote:
> Hello,
>
> I have difficulties in understanding how to use setResultsName
> correctly. The problem is illustrated in the code below:
> In the first version, r.BODY is empty. In the second version, it
> contains what I expected it to contain. But I am not sure what the
> difference is between these two versions?

setResultsName creates a copy of the object. The original is left 
unchanged. 

>
> Thanks for any insights.
>
> Best regards,
> Stefaan.
>
> ---
>
> import pyparsing as p
>
> s = """
> SECTION
> {
>    // {
>    if (1) { dosomething; } else { if (0) then { a; } else { b } }
>    printf ( "{" ); /* {
>    {
>    {
>    */
>    { nog; iets; }
> }
> """
>
> # VERSION 1
> section_body = p.Combine(p.nestedExpr("{","}",
> ignoreExpr=p.quotedString|p.cppStyleComment|p.cStyleComment))
> section_body.setParseAction(p.keepOriginalText)

This statement has no effect. The parser with the name attached is 
forgotten.
> section_body.setResultsName("BODY")

> grammar = p.CaselessKeyword("SECTION").suppress() + section_body
> r = grammar.parseString(s)
> print r.BODY
>
>
> # VERSION 2
> section_body = p.Combine(p.nestedExpr("{","}",
> ignoreExpr=p.quotedString|p.cppStyleComment|p.cStyleComment))
> section_body.setParseAction(p.keepOriginalText)
> grammar = p.CaselessKeyword("SECTION").suppress() + \
> section_body.setResultsName("BODY")
> r = grammar.parseString(s)
> print r.BODY
>
Kind regards,
Eike.