: startsWith? ( $1 $2 - f )
  withLength &swap dip 0 swap ^strings'getSubset compare ;

"abcdefghijkl" "abcde" startsWith?
"abcdefghijkl" "bcd" startsWith?

"abcdefghijkl" "bcd" ^strings'search
"abcdefghijkl" "zmq" ^strings'search

: endsWith? ( $1 $2 - f )
  swap withLength + over getLength - compare ;

"abcdefghijkl" "ijkl" endsWith?
"abcdefghijkl" "abc" endsWith?