SUBSTITUTE.html -- ACL2 Version 6.3

### SUBSTITUTE

substitute into a string or a list, using `eql` as test

    Major Section:  ACL2-BUILT-INS

`(Substitute new old seq)` is the result of replacing each occurrence of `old` in `seq`, which is a list or a string, with `new`.

The guard for `substitute` requires that either `seq` is a string and `new` is a character, or else: `seq` is a `true-listp` such that either all of its members are `eqlablep` or `old` is `eqlablep`.

`Substitute` is a Common Lisp function. See any Common Lisp documentation for more information. Since ACL2 functions cannot take keyword arguments (though macros can), the test used in `substitute` is `eql`.

To see the ACL2 definition of this function, see pf.