meanwhile from the heart of the sourcecode:
# takes a macro of regular expressions:
# /foo(bar)=[\w]+(bar1)=[\w]+foo1(bar2)=[\w]+(foo2)/
# with as many foo(s) and bar(s) as you want, where foo(s) and bar(s) are
# any regular expression and [\w]+ meaning any sequence of (a..z,A..Z,_).
# these will be used as variable name (key in a hash in most cases)
# to store any found data matching the regexp in brackets before
# each =[\w]+ (in this case all bars).
# the key substrings get removed (inc. =), creating a valid regular
# expression. furthermore any (foo) where foo is a defined key in
# %defined_regexps gets replaced by it's value
# brackets can be separated by '|' (pipe) as logical OR and they may be
# nested (should be recursive;-).
# e.g. /(bar)((foo1)|(foo2))=word/ would associate either foo1 or foo2