// character to remove
Set V[trimchar] "@"

// search first non-matching character
Set V[k] 1
label compare
if V[trimchar=&V[city](&V[k],&V[k])]
  Set V[k] &V[k] + 1
  goto compare
endif

// set new string
Set V[city2] "&V[city](&V[k],4000)"

// test message
Message "&V[city]\n&V[city2]"

Components
InputAssistant