Use of "id" as a variable name makes Boost unusable in Objective-C++

[stokestack@…]

I included a C++ object in an Objective-C++ file and compilation failed with "Expected primary-expression before..." It turns out that two relevant files were using "id" as a variable name. "id" is a keyword in Objective-C++.

Changing the variable name to "idx" (which appears to be more descriptive of its use anyway) eliminated the error.

Patch attached.

[Gavin Stokes <stokestack@…>]

patch to basic_regex_creator.hpp and perl_matcher_common.hpp

[John Maddock]

(In [61789]) Change "id" to "idx" to be Objective C++ compatible. Fixes #2306. Fixes #4132. Fixes #4191.