Anonymous user
Call a function: Difference between revisions
Added PicoLisp
m (→{{header|Ada}}) |
(Added PicoLisp) |
||
Line 271:
By default, arguments are passed readonly, which allows the implementation to decide whether pass-by-reference or pass-by-value is more efficient on a case-by-case basis. Explicit lvalue, reference, or copy semantics may be requested on a parameter-by-parameter basis, and the entire argument list may be processed raw if that level of control is needed.
=={{header|PicoLisp}}==
When calling a funcion in PicoLisp directly (does this mean "in a statement context"?), it is always surrounded by parentheses, with or without arguments, and for any kind of arguments (evaluated or not):
<lang PicoLisp>(foo)
(bar 1 'arg 2 'mumble)</lang>
When a function is used in a "first class context" (e.g. passed to another function), then it is not yet '''called'''. It is simply '''used'''. Technically, a function can be either a '''number''' (a built-in function) or a '''list''' (a Lisp-level function) in PicoLisp):
<lang PicoLisp>(mapc println Lst) # The value of 'printlin' is a number
(apply '((A B C) (foo (+ A (* B C)))) (3 5 7)) # A list is passed</lang>
Any argument to a function may be evaluated or not, depending on the function. For example, 'setq' evaluates every second argument
<lang PicoLisp>(setq A (+ 3 4) B (* 3 4))</lang>
i.e. the first argument 'A' is not evaluated, the second evaluates to 7, 'B' is not evaluated, then the fourth evaluates to 12.
=={{header|Tcl}}==
| |||