pocket-lambda-lib

Lambdas for C++98 - my very old code, for sentimental purposes only!

The idea was to be able to write code like:

find_if(vec.begin(), vec.end(), lambda(_$1 <= 2))
for_each(vec.begin(), vec.end(), lambda(cout << _$1 << "\n"));

sort(vec_of_ptrs.begin(), vec_of_ptrs.end(), lambda(*_$1 <= *_$2));
find_if(vec_of_ptrs.begin(), vec_of_ptrs.end(), lambda(_$1->getValue() != 7))
for_each(vec_of_ptrs.begin(), vec_of_ptrs.end(), lambda(delete _$1));

What finally got implemented is:

find_if(vec.begin(), vec.end(), _$1 <= 2);
for_each(vec.begin(), vec.end(), cout << _$1 << delay("\n")); 

sort(vec_of_ptrs.begin(), vec_of_ptrs.end(), *_$1 <= *_$2);
find_if(vec_of_ptrs.begin(), vec_of_ptrs.end(), _$1->*(&TestObj::getVal) != 7)

and, additionally:

// printing for members 
for_each(vec_of_ptrs.begin(), vec_of_ptrs.end(), cout << delay(" value=") << (_$1->*(&TestObj::getVal)) << delay(","));

// access to globals
for_each(vecx.begin(), vecx.end(), globvar(global_counter) += 5);

// currying
for_each(vec.begin(), vec.end(), bind(print_sinus, _$1 * 2));

// control structure(s)
for_each(vec.begin(), vec.end(), if_then(_$1 == 1, globvar(global_counter)++));
for_each(vec.begin(), vec.end(), if_then(_$1 == 7, _$1 = 9));

The lambda() expression wrapper wasn't done (no time) and I just forgot (!!) about delete support.

Explantions

I wrote a couple of blogposts explaining ideas behind this implementation:

• http://ib-krajewski.blogspot.com/2007/12/c-pocket-lambda-library.html
• http://ib-krajewski.blogspot.com/2008/01/c-pocket-lambda-library-part-2.html
• http://ib-krajewski.blogspot.com/2008/04/pocket-c-lambda-library-part-iia.html
• http://ib-krajewski.blogspot.com/2008/06/c-pocket-lambda-library-part-iii.html
• http://ib-krajewski.blogspot.com/2008/07/c-pocket-lambda-library-last.html

TODOs

• add the lambda() wrapper for expressions
• impl. support for deleting over pointers!
• add CMake support
• add C++98 build
• fix the problem with it == vec.end() not compiling!