Null cancelling movement script (source games)

autoexec.cfg

bind w +mfwd
bind s +mback
bind a +mleft
bind d +mright
 
alias +mfwd "-back;+forward;alias checkfwd +forward;"
alias +mback "-forward;+back;alias checkback +back;"
alias +mleft "-moveright;+moveleft;alias checkleft +moveleft;"
alias +mright "-moveleft;+moveright;alias checkright +moveright;"
alias -mfwd "-forward;checkback;alias checkfwd none;"
alias -mback "-back;checkfwd;alias checkback none;"
alias -mleft "-moveleft;checkright;alias checkleft none;"
alias -mright "-moveright;checkleft;alias checkright none;"
alias checkfwd none
alias checkback none
alias checkleft none
alias checkright none
alias none ""
bind "SPACE" "+jump"
bind "ctrl" "+duck"