Putting assertions in your code was always VERY important. I constantly find its importance in my coding. It is very important to always assert your variables\conditions along with the testing it ( 'if' statement ). Also, another common use is in an algorithm. it is important to assert different conditions which might define a state at a moment, a state which I know it should be false\true (when i mean a state i mean a condition composed of multiple variables, variables which might not be in the same scope but I expect some specific values). i am having situations where while coding, i come accross some asserts which make me say "wtf, how did that happen ?" and then i discover that the algo has some issues which were not obvious due to complexity (or my fatigue).

1. get the mozilla source code -------------------------------------------------- Get source code from https://developer.mozilla.org/en/Download_Mozilla_Source_Code Copy the firefox-1.5-source.tar.tar in e:\ Create a directory called e:\mozilla Extract the firefox-1.5.source.tar.tar into mozilla directory 2. install cygwin -------------------------------------------------- run http://www.cygwin.com/setup.exe choose the first type of install (the first form with the 3 radio-buttons) and choose "DOS" style line endings as you read the http://developer.mozilla.org/en/docs/Windows_Build_Prerequisites you see that you need to make sure that the cygwin packages include these: ash -- UNIX-like command line interpreter shell (Base category) coreutils -- GNU core utilities (includes fileutils, sh-utils, and textutils) (Base category) diffutils -- file comparison utility (Base category) findutils (Base category) gawk -- pattern matching language (Base and Interpretors categories) grep ...