The 'string=' [string-equal] function takes two string arguments. It checks to see if the string arguments have the same values. T is returned if 'string1' is equal to 'string2', NIL is returned otherwise. This test is case sensitive, the character '#\a' is different and of greater ASCII value than '#\A'.
The keyword arguments allow for accessing substrings within 'string1' and 'string2'. The keyword arguments each require a keyword ':start1', ':end1', ':start2' or ':end2' and a single integer expression as a pair with the keyword first and the integer second. The pairs may be in any order. The ':startN' keywords specify the starting offset of the substring. A value of 0 starts the string at the beginning [no offset]. The ':endN' keywords specify the ending offset of the substring. A value of 3 ends the string after the 3rd character [an offset of 3 characters].
(string= "a" "b") ; returns NIL (string= "a" "a") ; returns T (string= "a" "A") ; returns NIL (string= "A" "a") ; returns NIL (string= "abc" "abc ") ; returns NIL (string= "J Smith" "K Smith" :start1 1 :start2 1) ; strip off the first chars ; returns T (string= "abc" "123456789" :end2 3 :end1 3) ; leave just the first 3 chars ; returns NIL
See the
string=
function in the