Re: [PATCH] gnu: wxwidgets: enable advanced (!) regular expressions.

[Danny Milosavljevic <dannym@scratchpost.org>]

Hi,

some more docs about the so-called "advanced" regular expressions needed by KiCad and wxRegEx in general:

http://wxd.sourceforge.net/wxWidgets-2.5.3/docs/html/wx/wx_wxregex.html

The "advanced" regular expression features (on top of extended regular expressions) are:
- Escapes: \a \b \n \r etc have the usual C meaning (bell, backspace, newline, carriage return etc)
- Class Shorthands: \d is the same as [[:digit:]]
- positive lookahead
- negative lookahead

The places in KiCad 4.0.1 where they are used are:

./eeschema/class_netlist_object.cpp:static wxRegEx busLabelRe( wxT( "^([^[:space:]]+)(\\[[\\d]+\\.+[\\d]+\\])$" ), wxRE_ADVANCED );
./pcbnew/dialogs/dialog_fp_lib_table.cpp:        wxRegEx re( wxT( ".*?\\$\\{(.+?)\\}.*?" ), wxRE_ADVANCED );
./pcbnew/netlist_reader.cpp:    wxRegEx reOrcad( wxT( "(?i)[ ]*\\([ \t]+{+" ), wxRE_ADVANCED );
./pcbnew/netlist_reader.cpp:    wxRegEx reLegacy( wxT( "(?i)#[ \t]+EESchema[ \t]+Netlist[ \t]+" ), wxRE_ADVANCED );
./pcbnew/netlist_reader.cpp:    wxRegEx reKicad( wxT( "[ ]*\\(export[ ]+" ), wxRE_ADVANCED );

As you can see the "advanced" features are actually used in the eeschema class_netlist_object (trivially, just the shorthand) and in the netlist reader in two places (Escapes and some mysterious "(?i)" moniker - see http://www.regular-expressions.info/modifiers.html . Not sure whether that would be supported in POSIX extended regular expressions). As far as I can see the other places don't actually use the "advanced" features. Note that POSIX extended regular expressions are "almost an exact" subset of "advanced regular expressions", according to the docs.