Name: call

Type: command

Syntax: call <handlerName> [of <objectRef>]

Summary:
<execute|Executes> the specified <handler> in any <object(glossary)|object's>
<script>. 

Introduced: 1.0

OS: mac, windows, linux, ios, android

Platforms: desktop, server

Example:
call "mouseUp"

Example:
call "mouseUp" of button 1 of card 1

Parameters:
handlerName:
Any handler in the script of the specified object, along with
any parameters that handler requires, separated by commas. The entire 
handler including parameters must be enclosed in quotes.

objectRef:
Any <object reference>. If no object is specified, LiveCode uses
the current object.

Description:
Use the <call> <command> to use a <handler> that's not in the normal 
<message path>.

The <call> <command> sends a <handler> <message> to the 
<object(glossary)>. If the <script> of the <object(glossary)> doesn't 
<trap> the <handler> <message>, the <message> is <pass|passed> to the 
next <object(glossary)> in the <object(glossary)|object's> <message path>.

When executing a <handler> invoked by the <call> <command> the <defaultStack> 
remains the same as it was when the <call> <command> was issued. Therefore 
any <object reference|object references> in the called <handler> are evaluated 
in the context of the <call> <command> that invoked the handler.  For example,
button 3 may commonly refer to button 3 of the current card of the stack
from which the target <handler> was called.

This differs from the <send> <command> which temporarily changes the 
context so that <object reference|object references> are evaluated 
in the context of the <object(glossary)> containing the target <handler>.

>*Tip:* If a <handler> contains complex <parameter|parameters>, 
especially if some <parameter|parameters> contain 
<double quote|double quotes>, it may be simpler to put the <message> 
name and <parameter|parameters> into a <variable>, then use the name of 
the <variable> in the <call> <statement>.

References: command (glossary), defaultStack (property), do (command), 
double quote (glossary), execute (glossary), handler (glossary), 
insert script (command), message (glossary), 
message path (glossary), object (glossary), 
object reference (glossary), parameter (glossary), 
params (function), pass (control structure), pass (glossary), 
script (property), send (command), start using (command), 
statement (glossary), trap (glossary), value (function), 
variable (glossary)

Tags: messages