====== Suppressing source code in Python warnings ======

Python has a great way to print warnings without raising an exception (which would halt the program).  However, it prints the line of source code that generated the warning, which is a) unnecessarily verbose, and b) universally useless because it's always just the call to the warnings module which you're already looking at the output of.  Suppressing it is somewhat complex, but easy to copy/paste; just put this verbatim at the top of your file (not inside a function, or you'll wind up with recursion issues):

<code python>
import warnings

formatwarning_upstream = warnings.formatwarning
def my_formatwarning(message, category, filename, lineno, line=None):
    return(formatwarning_upstream(message, category, filename, lineno, line=''))
warnings.formatwarning = my_formatwarning

</code>

Now you can call warn() just like you normally would (the second example just restates the defaults):

<code python>
warnings.warn("Something isn't quite right, but we don't have to abort over it.")
warnings.warn("Something isn't quite right, but we don't have to abort over it.", UserWarning, stacklevel=1)
</code>

====== Indirect variables in shell scripts ======

Normally, you'd use an associative array for this (including BASH) instead of manually embedding a variable in another variable, but this solution works in POSIX environments like regular Bourne shell (and BASH's emulation of it):

<code bash>
favorite_color_joe=gold
favorite_color_jane=blue

person=${1}

target_interface=`eval echo \$favorite_color_${person}`
</code>