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bug#14892: [PATCH] Enhance Elisp compare functions (< <= > >=) to take v


From: Barry OReilly
Subject: bug#14892: [PATCH] Enhance Elisp compare functions (< <= > >=) to take var args
Date: Tue, 10 Sep 2013 10:54:02 -0400

> Looking at your patch a second time, I don't see how/where it
> handles (< a b c) in byte-compiled code: the byte-codes only
> handle 2-arguments, and the byte-compiler is left unchanged.

(disassemble (byte-compile (lambda () (< x y))))
byte code:
  args: nil
0       varref    x
1       varref    y
2       lss      
3       return   

(disassemble (byte-compile (lambda () (< x y z))))
byte code:
  args: nil
0       constant  <
1       varref    x
2       varref    y
3       varref    z
4       call      3
5       return   

So it works with many args, it just byte compiles to a general
function call rather than to a specific comparison bytecode.

I had considered this before submitting the patch, but decided it
might be a premature optimization to extend the byte compiler in
this way. There are no users of more than 2 args to start with.

'make check' runs the new data-tests as byte compiled, so it has
been tested.


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