PLOGHELP NAME                                   Robert Duncan, June 1988


    ?- name(Item, CharList).


Conversion between atomic terms and character strings.


In this goal, CharList is the list of ASCII characters which make up the
atomic term Item. For instance:

    ?- name(example, "example").
    yes

By leaving CharList wholly or partly uninstantiated, it is possible to
decompose an atom into its constituent characters, as in:

    ?- name(example, X).
    X = [101, 120, 97, 109, 112, 108, 101] ?
    yes

Alternatively, if Item is left uninstantiated, then an atom will be
constructed from CharList and assigned to Item.

    ?- name(X, "example").
    X = example ?
    yes

In this case, it is an error for CharList to be anything other than a
proper string.

As an example, here is the definition of a predicate which removes the
extension from a file name, i.e. everything after the "." character:

    basename(F, F1) :-
        name(F, S),
        append(S1, [46|Ext], S),    % 46 is the ASCII code for "."
        name(F1, S1).

    ?- basename('temp.pl', X).
    X = temp ?
    yes

Item may be any atomic term, not just a pure atom. This includes
numbers, together with any data objects imported from other languages
(such as Lisp or POP-11). In these cases, CharList will be unified with
the characters which make up the printing representation of Item. For
example:

    ?- name(12.33, X).
    X = [49, 50, 46, 51, 51] ?
    yes

In general of course, it is impossible to do the inverse of this
decomposition, as an arbitrary data object cannot possibly be
reconstructed simply from its printing representation. However, a
special case is made for integers: whenever CharList contains only digit
characters, Item will be instantiated to the integer value of the digit
string, as in:

    ?- name(N, "999"), integer(N).
    N = 999 ?
    yes


-- RELATED DOCUMENTATION ----------------------------------------------

PLOGHELP * STRINGS
    Strings in Prolog

PLOGHELP * UNIV
    Conversion between complex terms and lists

--- C.all/plog/help/name -----------------------------------------------
--- Copyright University of Sussex 1988. All rights reserved. ----------