User Manual

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CATC MERLIN’S WAND 1.22 APPENDIX D
User’s Manual CATC Scripting Language
D.11 Functions
A function is a named statement or a group of statements that are executed
as one unit. All functions have names. Function names must contain only
alphanumeric characters and the underscore ( _ ) character, and they cannot
begin with a number.
A function can have zero or more parameters, which are values that are
passed to the function statement(s). Parameters are also known as
arguments. Value types are not specified for the arguments or return values.
Named arguments are local to the function body, and functions can be called
recursively.
The syntax for a function declaration is
name(<parameter1>, <parameter2>, ...)
{
<statements>
}
The syntax to call a function is
name(<parameter1>, <parameter2>, ...)
So, for example, a function named add can be declared like this:
add(x, y)
{
return x + y;
}
and called this way:
add(5, 6);
This would result in a return value of 11.
Every function returns a value. The return value is usually specified using a
return statement, but if no return statement is specified, the return
value will be the value of the last statement executed.
Arguments are not checked for appropriate value types or number of
arguments when a function is called. If a function is called with fewer
arguments than were defined, the specified arguments are assigned, and the
remaining arguments are assigned to null. If a function is called with more
arguments than were defined, the extra arguments are ignored. For example,
if the function add is called with just one argument