Monkey patching a function in bash.

monkey-patch

#! /usr/bin/env bash
#
# Monkey patching a function in bash. Why.

patch() {
    new_guy=$(declare -f $1)
    new_guy=${new_guy##$1*\{}
    new_guy=${new_guy/\}/}
    old_guy=$(declare -f $2)
    old_guy=${old_guy/$2*{/}
    old_guy=${old_guy/\}/}
    eval "$2() { $new_guy $old_guy }"
}

search() {
    echo "do the original thing"
}

sneaky() {
    echo "wait, do this first"
}

patch sneaky search
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