Functions in a Block

I’m still working on my little Rascal AS compiler and in doing so I encountered some ActionScript strangeness while figuring out some scope rules. Take for example this piece of code:

bc[as].. if ( true )
{
trace ( “entering true clause” ) ;

function hello ( sender : String )
{
trace ( “hello from ” + sender ) ;
}

trace ( “hello function = ” + hello ) ;
hello ( “block” ) ;
}
hello ( “top-level” ) ; // expecting failure: out of (block) scope.

p. According to the ECMAScript 4 standard, this is valid code. One would expect the folowing traced output:

entering true clause
hello function = [ type Function ]
hello from block

However, the actual traced output is:

entering true clause
hello function = undefined

Go figure.. Perhaps I’m missing something, but as it seems Flash ActionScript does not allow named function definitions within a Block. Effectively this would mean that named functions can only be declared at top level (either at a frame or in a class definition’s body) or nested within another function.

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Published:
Monday, August 8th, 2005 at 11:40 am
Author:
Ryko
Category:
Flash