string_concat/3

Availability:built-in

string_concat(?String1, ?String2, ?String3)

Similar to atom_concat/3, but the unbound argument will be unified with a string object rather than an atom. Also, if both String1 and String2 are unbound and String3 is bound to text, it breaks String3, unifying the start with String1 and the end with String2 as append does with lists. Note that this is not particularly fast on long strings, as for each redo the system has to create two entirely new strings, while the list equivalent only creates a single new list-cell and moves some pointers around.