migragen.sh

#!/bin/bash

[ "$(type -t make:migration)" = "alias" ] && unalias make:migration

comment="# Add shortcut for generating CodeIgniter migrations."
alias="alias make:migration='php index.php migrate generate'"

if grep -R -zoP "\n$comment\n$alias" ~/.bashrc; then
  sed "s/$comment//g" ~/.bashrc > tmp && sed "s/$alias//g" tmp > ~/.bashrc
  sed -i -e :a -e '/^\n*$/{$d;N;}/\n$/ba' ~/.bashrc
else
  echo "\n$comment\n$alias" >> ~/.bashrc
fi