>>>>> "J" == Jeremy Henty <jeremy / chaos.org.uk> writes: J> * If I replace rb_f_lambda() by rb_block_proc() will the code break J> when built under Ruby 1.6.x ? yes, J> * If I have to #ifdef a macro to support both 1.6.x and 1.8.x , what's J> a clean way to do it? Does extconf.rb support this, or do I have to J> roll my own? svg% /usr/bin/ruby -vrmkmf -e 'have_func("rb_block_proc")' ruby 1.8.2 (2004-12-25) [i686-linux] checking for rb_block_proc()... yes svg% svg% ./ruby -vrmkmf -e 'have_func("rb_block_proc")' ruby 1.6.8 (2002-12-24) [i686-linux] checking for rb_block_proc()... no svg% Guy Decoux