Comparison of 'which', 'command -v', 'type' and 'hash'

existence.zsh

query=vim
time bash -c "for i in {0..1000}; do which $query; done >/dev/null 2>&1"
time bash -c "for i in {0..1000}; do command -v $query; done >/dev/null 2>&1"
time bash -c "for i in {0..1000}; do type $query; done >/dev/null 2>&1"
time bash -c "for i in {0..1000}; do hash $query; done 2>/dev/null"
time zsh -c "for i in {0..100000}; do which $query; done >/dev/null 2>&1"
time zsh -c "for i in {0..100000}; do command -v $query; done >/dev/null 2>&1"
time zsh -c "for i in {0..100000}; do type $query; done >/dev/null 2>&1"
time zsh -c "for i in {0..100000}; do hash $query; done 2>/dev/null"

Reference: http://stackoverflow.com/questions/592620/check-if-a-program-exists-from-a-bash-script