Re: are there implementation reasons for not providing a break statement in an imperative language?

Ira Baxter <idbaxter@semdesigns.com> wrote:
(snip)


> Another alternative, much better IMHO, is labelled-block exits.
> Blocks may have labels. An exit <label> is allowed anywhere inside
> the block, and passes control to statement following the end. The
> above block would be recoded as:


> x: do {
> resource = getResource(counter);
> if (resource.isOk())
> exit x;
> releaseResource(resource);
> counter.increment();
> }


I suppose, but I am not sure it is any easier to read.


With GOTO, at least the statement you are looking for has the
specified label. In this case, when reading the code, first you have
to find the label x, then the end of the block that has that label.
For big blocks, that can be a lot of looking.


Now, many editors can find the } that matches a {, which helps
while in the editor, but not so much reading.


It does help with the "add a new block" later (that I snipped)
problem, but not much else.


-- glen

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