MACROMEDIA DIRECTOR MX-LINGO DICTIONARY, Руководство пользователя

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return (keyword)
Syntax
return expression
Description
Keyword; returns the value of
expression
and exits from the handler. The
expression
argument
can be any Lingo value.
When calling a handler that serves as a user-defined function and has a return value, you must use
parentheses around the argument lists, even if there are no arguments, as in the
diceRoll
function
handler discussed under the entry for the
result
function.
The function of the
return
keyword is similar to that of the
exit
command, except that
return
also
returns a value to whatever called the handler. The
return
command in a handler immediately
exits from that handler, but it can return a value to the Lingo that called it.
The use of
return
in object-oriented scripting can be difficult to understand. It’s easier to start by
using
return
to create functions and exit handlers. Later, you will see that the
return me
line in an
on new
handler gives you a way to pass back a reference to an object that was created so it can be
assigned to a variable name.
The
return
keyword isn’t the same as the character constant
RETURN
, which indicates a carriage
return. The function depends on the context.
To retrieve a returned value, use parentheses after the handler name in the calling statement to
indicate that the named handler is a function.
To see an example of
return (keyword)
used in a completed movie, see the Parent Scripts movie in
the Learning/Lingo Examples folder inside the Director application folder.
Example
This handler returns a random multiple of 5 between 5 and 100:
on getRandomScore
theScore = 5 * random(20)
return theScore
end getRandomScore
Call this handler with a statement similar to the following:
set thisScore to GetRandomScore()
In this example, the variable
thisScore
is assigned the return value from the function
GetRandomScore
. A parent script performs the same function: by returning the object reference, the
variable name in the calling code provides a handle for subsequent references to that object.
See also
result
,
RETURN (constant)