Re: [patch] continue statement

[Chris Marrin <chris@...>]

Shannon Stewman wrote:
> On Mon, Sep 12, 2005 at 06:47:34PM +0200, Wolfgang Oertl wrote:
>
>
> > I find that without a "continue" statement some loops soon have
> > deeply nested if/else statements in them.  This patch adds
> > them to Lua 5.1-alpha.  It's also on the PowerPatches page of
> > the Lua wiki.
>
>
> Here is another example where a standard way to do non-local exit would
> help.  The syntax was proposed in
> http://lua-users.org/lists/lua-l/2005-08/msg00357.html

Javascript (and others) do this with labelled break and continue. It 
lets you do this:

outer_loop:
  for(i = 0; i < 10; i++) {
    for(j = 0; j < 10; j++) {
      if (f(i,j) > 0) break;               // break out of inner loop
      if (g(i,j) > 0) continue outer_loop; // restart outer loop
      if (h(i,j) > 0) break outer_loop;    // break out of outer loop
    }
  }

It's nice looking syntax IMHO. And it's very safe since the label must 
be on a looping statement or a compile time error is generated.

--
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