lhunath 1187990841 learn shell keyword similar to (but more powerful than) the [ command. See http://wooledge.org/mywiki/BashFAQ#faq31 and http://wooledge.org/mywiki/BashGuide#Bash_Tests
lhunath 1187990899 forget
han-solo 1685796725 learn !learn a
han-solo 1685796743 forget