Passing an array to a function/handler

Dar Scott dsc at
Wed Jun 11 20:06:00 EDT 2003

On Wednesday, June 11, 2003, at 05:27 PM, Huisingh, Larry R wrote:

> I can't tell from the docs...Can you pass an array to a function (or 
> handler)? 

Yes, but arrays do not have full value semantics.

You can pass an array as a parameter.

You can return an array as the "value" of a function, but that cannot 
be directly a parameter to another function or handler and it cannot be 
[ ]'d.  You cannot create array expressions.

This means you can use an array to represent interesting data, but the 
fact that it is an array cannot be hidden.  (Because of that, you can 
feel free to use reference variables as parameters, should you work 
with very large arrays, even when you don't modify the variable--you 
can't have an array expression as a parameter, anyway.)

Try this:

function fetch e, k
   return e[k]
end fetch

function makeA
   local x
   put "abc" into x["a"]
   put "a" into x["b"]
   return x
end makeA

on mouseUp
   local y
   put "eee" into y["v"]
   put fetch(y,"v") & LF into field "Report"
   put fetch(makeA(),"a") & LF after field "Report"
   put makeA() into y
   put fetch(y,"b") & LF after field "Report"
end mouseUp

This produces this:


It does not produce this:

Also, arrays will be empty whenever a string conversion occurs.  This 
includes "send".

Dar Scott
Revolution Lurker who needs arrays.  Or, at least, a bonus.

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