string/= string1 string2 &key start1 end1 start2 end2	mismatch-index
string< string1 string2 &key start1 end1 start2 end2	mismatch-index
string> string1 string2 &key start1 end1 start2 end2	mismatch-index
string<= string1 string2 &key start1 end1 start2 end2	mismatch-index
string>= string1 string2 &key start1 end1 start2 end2	mismatch-index

string-equal string1 string2 &key start1 end1 start2 end2    generalized-boolean

string-not-equal string1 string2 &key start1 end1 start2 end2	mismatch-index
string-lessp string1 string2 &key start1 end1 start2 end2	mismatch-index
string-greaterp string1 string2 &key start1 end1 start2 end2	mismatch-index
string-not-greaterp string1 string2 &key start1 end1 start2 end2	mismatch-index
string-not-lessp string1 string2 &key start1 end1 start2 end2	mismatch-index

string2 - a string designator.

start1, end1 - bounding index designators of string1. The defaults for start and end are 0 and nil, respectively.

start2, end2 - bounding index designators of string2. The defaults for start and end are 0 and nil, respectively.

generalized-boolean - a generalized boolean.

mismatch-index - a bounding index of string1, or nil.

A string a is equal to a string b if it contains the same number of characters, and the corresponding characters are the same under char= or char-equal, as appropriate.

A string a is less than a string b if in the first position in which they differ the character of a is less than the corresponding character of b according to char< or char-lessp as appropriate, or if string a is a proper prefix of string b (of shorter length and matching in all the characters of a).

The equality functions return a generalized boolean that is true if the strings are equal, or false otherwise.

The inequality functions return a mismatch-index that is true if the strings are not equal, or false otherwise. When the mismatch-index is true, it is an integer representing the first character position at which the two substrings differ, as an offset from the beginning of string1.

The comparison has one of the following results:

• string=

  string= is true if the supplied substrings are of the same length and contain the same characters in corresponding positions; otherwise it is false.

• string/=

  string/= is true if the supplied substrings are different; otherwise it is false.

• string-equal

  string-equal is just like string= except that differences in case are ignored; two characters are considered to be the same if char-equal is true of them.

• string<

  string< is true if substring1 is less than substring2; otherwise it is false.

• string>

  string> is true if substring1 is greater than substring2; otherwise it is false.

• string-lessp, string-greaterp

  string-lessp and string-greaterp are exactly like string< and string>, respectively, except that distinctions between uppercase and lowercase letters are ignored. It is as if char-lessp were used instead of char< for comparing characters.

• string<=

  string<= is true if substring1 is less than or equal to substring2; otherwise it is false.

• string>=

  string>= is true if substring1 is greater than or equal to substring2; otherwise it is false.

• string-not-greaterp, string-not-lessp

  string-not-greaterp and string-not-lessp are exactly like string<= and string>=, respectively, except that distinctions between uppercase and lowercase letters are ignored. It is as if char-lessp were used instead of char< for comparing characters.

 (string= "foo" "foo")  true
 (string= "foo" "Foo")  false
 (string= "foo" "bar")  false
 (string= "together" "frog" :start1 1 :end1 3 :start2 2)  true
 (string-equal "foo" "Foo")  true
 (string= "abcd" "01234abcd9012" :start2 5 :end2 9)  true
 (string< "aaaa" "aaab")  3
 (string>= "aaaaa" "aaaa")  4
 (string-not-greaterp "Abcde" "abcdE")  5
 (string-lessp "012AAAA789" "01aaab6" :start1 3 :end1 7
                                      :start2 2 :end2 6)  6
 (string-not-equal "AAAA" "aaaA")  false