Comments on: Function Variables http://jacksondunstan.com/articles/247 Mastering AS3 Mon, 14 May 2012 17:02:12 +0000 hourly 1 http://wordpress.org/?v=3.3.1 By: jackson http://jacksondunstan.com/articles/247/comment-page-1#comment-496 jackson Wed, 10 Feb 2010 18:54:49 +0000 http://jacksondunstan.com/?p=247#comment-496 Good point. You're spot on in this clarification. Good point. You’re spot on in this clarification.

]]> By: Sindisil http://jacksondunstan.com/articles/247/comment-page-1#comment-493 Sindisil Wed, 10 Feb 2010 14:30:18 +0000 http://jacksondunstan.com/?p=247#comment-493 Actually, block scoped local variables are allowed in C89 (aka ANSI C), as well. In fact, though my 1st Ed. K&R isn't at hand to check, I seem to remember that C has <b>always</b> allowed block scoped local variables. C does require the declarations to be at the <strong>top</strong> of the block, though. What C99 added was local variables with less than block scope, as in C++. In other words, the ability to declare a variable right before use. Local variable's scope is then from the point of declaration to the end of the innermost containing block. Sorry for the post necromancy, but you've got a valuable blog here & I though this correction might be useful to a new reader. Actually, block scoped local variables are allowed in C89 (aka ANSI C), as well.

In fact, though my 1st Ed. K&R isn’t at hand to check, I seem to remember that C has always allowed block scoped local variables.

C does require the declarations to be at the top of the block, though.

What C99 added was local variables with less than block scope, as in C++. In other words, the ability to declare a variable right before use. Local variable’s scope is then from the point of declaration to the end of the innermost containing block.

Sorry for the post necromancy, but you’ve got a valuable blog here & I though this correction might be useful to a new reader.

]]> By: jackson http://jacksondunstan.com/articles/247/comment-page-1#comment-28 jackson Wed, 16 Sep 2009 20:17:59 +0000 http://jacksondunstan.com/?p=247#comment-28 As a C99/C++ programmer, I really miss block-level scoping. I don't know why they didn't do as you suggest and handle it in the compiler. After all, there is no block-level scoping in the x86 machine code C/C++ compiles down to, so I don't think Adobe has much of an excuse here. As a C99/C++ programmer, I really miss block-level scoping. I don’t know why they didn’t do as you suggest and handle it in the compiler. After all, there is no block-level scoping in the x86 machine code C/C++ compiles down to, so I don’t think Adobe has much of an excuse here.

]]> By: Troy Gilbert http://jacksondunstan.com/articles/247/comment-page-1#comment-23 Troy Gilbert Wed, 16 Sep 2009 20:01:31 +0000 http://jacksondunstan.com/?p=247#comment-23 C originally worked this way. I believe it was C99 (and C++) that first allowed block-level scope. From what I understand, at the bytecode level there is no block-level scope, thus AS3 reflects that literally (even though I do know the compiler could handle that detail for us internally). C originally worked this way. I believe it was C99 (and C++) that first allowed block-level scope.

From what I understand, at the bytecode level there is no block-level scope, thus AS3 reflects that literally (even though I do know the compiler could handle that detail for us internally).

]]> By: jackson http://jacksondunstan.com/articles/247/comment-page-1#comment-13 jackson Wed, 16 Sep 2009 17:49:10 +0000 http://jacksondunstan.com/?p=247#comment-13 Thanks for the link. It's good to see that Adobe has at least documented what is going on. I still wonder <em>why</em> they chose to do this though. I find that it is almost always more confusing and more error prone than block-level scoping. Thanks for the link. It’s good to see that Adobe has at least documented what is going on. I still wonder why they chose to do this though. I find that it is almost always more confusing and more error prone than block-level scoping.

]]> By: Robert Penner http://jacksondunstan.com/articles/247/comment-page-1#comment-12 Robert Penner Wed, 16 Sep 2009 17:45:29 +0000 http://jacksondunstan.com/?p=247#comment-12 AS3 hoists variable declarations to the top of the function: http://help.adobe.com/en_US/ActionScript/3.0_ProgrammingAS3/WS5b3ccc516d4fbf351e63e3d118a9b90204-7f9d.html AS3 hoists variable declarations to the top of the function:

http://help.adobe.com/en_US/ActionScript/3.0_ProgrammingAS3/WS5b3ccc516d4fbf351e63e3d118a9b90204-7f9d.html

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