IMPORTANT: Individual phrases for Normal Search should be enclosed in double quotes ("). Individual phrases for Regular Expression should be enclosed in backticks (`). See below for more information.
Normal Search
The normal search does a literal match for one or more terms. For example,
whiskey xray
will find pages with "whiskey" and/or "xray" in them. If you quote several words ("whiskey xray"), they will be searched for together as a phrase. So
uniform "kilo bravo"
will find pages with "uniform" and/or "kilo bravo" in them. The results are ranked by the number of hits, but pages which contain ALL terms are favored. So if you search for
Bob Doug
a page which contains "bob" twice and "doug" once will rank higher than a page containing "bob" a hundred times but no doug.
Regular Expression
These are PCRE's ("Perl Compatible Regular Expressions"), a nicer version of POSIX "grep" style regular expressions. For example:
\bAmerica\b
will match "America" as a discrete word -- it will NOT match "Americana" or "Americanism" (but it will match "Pan-american"). If you've never used regexps before, there is a simple guide geared to search engine usage here with useful examples.
You will be warned if your regexp is invalid. Using stuff like .*, even in the non-greedy form .*?, may not be very useful. If you want to look for one thing or another indefinitely seperated, it's better to use multiple terms.
MULTIPLE TERMS: The regular expression search does this the same way as the normal search, except `backticks` are used to indicate whole phrases instead of double quotes. So:
\buniform\b `(kilo|pound) bravo` whales?
Will find pages with "\buniform\b", "(kilo|pound) bravo", and/or "whales?" in them.
Pages are ranked the same way they are for the normal search.
Please send questions, bug reports, etc. about the site-search to: rms at gnu dot org