string_concat(?String1, ?String2, ?String3)

String1

String or variable.

String2

String or variable.

String3

String or variable.

Description

Used to find all possible solutions for the concatenation of String1 and String2 to make String3.

Note that if String1 and String2 are instantiated, it is more efficient to use the predicate concat_strings/3.

This predicate is an alias for append_strings/3.

Modes and Determinism

• string_concat(+, +, -) is det
• string_concat(+, -, +) is det
• string_concat(-, +, +) is det
• string_concat(-, -, +) is multi

Exceptions

(5) type error

One (or more) of the arguments is instantiated, but not to a string.

(4) instantiation fault

String3 and at least one other argument are uninstantiated.

Examples

Success:
      string_concat("a",B,"abc"). (gives B = "bc").
      string_concat(A,B,"a").     (gives A=""  B="a";
                                          A="a" B="").
Fail:
      string_concat("a","b","abc").
Error:
      string_concat(A,"bc",C).        (Error 4).
      string_concat(5,B,C).           (Error 5).
      string_concat(A,'me',"meme").   (Error 5).

See Also