PWchange: CHANGE (SOME ASPECTS OF) AN OBJECT
This chapter explains the use of the PWchange command.
Purpose
With this command you can change some aspect of an object, adding something
to it, or altering something within it. It can happen that, due to a
user-defined action, you would like to make some modification to an object.
For example, you might want to change the keypress for a QUIT item in an
outline according to some runtime preference expressed by the user. You
would then change the outline so that the quit keypress becomes (say) 'x'
instead of ESC.
In some other cases, the change command is also used to actually obtain
something from the object. Normally, this would be done with the PWquery
function, but under some circumstances (as documented with the description
of each type/tag) the PWchange command is
used.
Syntax
PWchange
object,tag, [,tags...]
The object is the object to change, the tag is the tag which adds to, or
changes, the object. For a more detailed explanation of what tags are, you
should refer to the PWcreate function.
There is also a function called PWchange%. This does exactly the same as
PWchange, but, instaed of interrupting the program with an error if there
is an unrecognized tag, it returns a value: 0 means everything went ok, any
other value means that there was an error.
PROGS, Professional & Graphical Software
last edited 1997 Jun 06 (wl)