======Function Call Expressions======

Starting with version 1.0.7 functions may be called in 'function call syntax' as a value expression.
The previous calling convention (as described above) is "procedural" where function calls behave like commands.
Function Call Expressions look like and behave more like traditional language functions.
The return value can be any value type (including XDM values such as sequences, elements etc). Evaluating a function call evaluates to the return value.

Arguments are passed in Function Call expressions with ( arglist ).

For example, A function that concatenates 2 arguments separated by ":"

%%(shell)
function concat()
{
return "$1:$2" ;
}

echo concat(hello world)
%%

Result
%%
hello:world
%%

Function call expressions can be assigned to variables

%%
a=concat(hello world)
echo $a
%%

Since they are value expressions they can nest and recurse.

%%
a=concat( concat(this that) another)
%%
Result
%%
this:that:anoother
%%


Arguments are expanded exactly like command execution. The output of the function is shared with the output of the calling shell the same as in procedural calling.

Example

%%(shell)
function list()
{
echo $*
return $#
}

a=list(*.c)
echo There were $a .c files
%%

Result

%%
foo.c bar.c spam.c
There were 3 .c files
%%


===Java Objects===
Functions can consume, operate on, and produce [[JavaObjects Java Objects]]

Example:
Note this demonstrates types of function call syntax and passing java objects.

%%
function today()
{
return jnew( java.util.Date )
}

function printDate()
{
date=$1
echo date.toString()
}

printDate today()

%%

Result
%%
Thu Nov 18 11:15:43 EST 2010
%%




----

[[CoreSyntax]]
[[Commands]]
[[Functions]]
[[SyntaxFunction]]