Comments on: Pickle: An interesting stack language http://peadrop.com/blog/2007/06/18/pickle-an-interesting-stack-language/ Random Computer Musings Mon, 06 Oct 2008 19:56:21 +0000 http://wordpress.org/?v=2.5.1 By: Georg http://peadrop.com/blog/2007/06/18/pickle-an-interesting-stack-language/#comment-146 Georg Fri, 20 Jul 2007 13:52:27 +0000 http://peadrop.com/blog/2007/06/18/pickle-an-interesting-stack-language/#comment-146 <p>Nice post! I do hope you add builtin support for sets (and frozensets) to the unified pickle for Py3k, while you're at it :)</p> Nice post! I do hope you add builtin support for sets (and frozensets) to the unified pickle for Py3k, while you’re at it :)

]]> By: Alexandre http://peadrop.com/blog/2007/06/18/pickle-an-interesting-stack-language/#comment-148 Alexandre Wed, 20 Jun 2007 14:46:30 +0000 http://peadrop.com/blog/2007/06/18/pickle-an-interesting-stack-language/#comment-148 <p>Eduardo, it is because I haven't asked yet, since I don't know whom to ask. I am already on <a href="http://soc.python.org/" rel="nofollow">Planet Python/SoC</a>, though.</p> Eduardo, it is because I haven’t asked yet, since I don’t know whom to ask. I am already on Planet Python/SoC, though.

]]> By: Eduardo Padoan http://peadrop.com/blog/2007/06/18/pickle-an-interesting-stack-language/#comment-147 Eduardo Padoan Wed, 20 Jun 2007 03:41:01 +0000 http://peadrop.com/blog/2007/06/18/pickle-an-interesting-stack-language/#comment-147 <p>Why isn't your blog aggregated at Planet Python yet? :) It seems that you are learning some cool things with GSoC! Bad suggestion: you could receive 2 strings in my_if and eval then, to make it lazy and usable in a pickle stream.</p> Why isn’t your blog aggregated at Planet Python yet? :) It seems that you are learning some cool things with GSoC! Bad suggestion: you could receive 2 strings in my_if and eval then, to make it lazy and usable in a pickle stream.

]]> By: Alexandre http://peadrop.com/blog/2007/06/18/pickle-an-interesting-stack-language/#comment-155 Alexandre Tue, 19 Jun 2007 15:47:52 +0000 http://peadrop.com/blog/2007/06/18/pickle-an-interesting-stack-language/#comment-155 <p>Thanks everyone for your cheerful comments. I am surprised by how this post caught up. I guess I share my knowledge more often, then.</p> <p>Arnar, yes indeed, that is a solution. That wouldn't be usable in a pickle stream, however, since you cannot create functions in them.</p> Thanks everyone for your cheerful comments. I am surprised by how this post caught up. I guess I share my knowledge more often, then.

Arnar, yes indeed, that is a solution. That wouldn’t be usable in a pickle stream, however, since you cannot create functions in them.

]]> By: Arnar http://peadrop.com/blog/2007/06/18/pickle-an-interesting-stack-language/#comment-154 Arnar Tue, 19 Jun 2007 09:27:35 +0000 http://peadrop.com/blog/2007/06/18/pickle-an-interesting-stack-language/#comment-154 <p>Cool article.</p> <p>The problem with my_if is that it's not lazy. You can use lambda to make it lazy:</p> <pre><code class="prettyprint">def my_if(cond, then_val, else_val): if cond: return then_val() else: return else_val() def factorial(n): return my_if(n==1, lambda: 1, lambda: n * factorial(n-1))</code></pre> <pre><code>>>> factorial(2) 2 >>> factorial(15) 1307674368000L</code></pre> Cool article.

The problem with my_if is that it’s not lazy. You can use lambda to make it lazy:

def my_if(cond, then_val, else_val):
    if cond:
        return then_val()
    else:
        return else_val()

def factorial(n):
    return my_if(n==1, lambda: 1, lambda: n * factorial(n-1))
>>> factorial(2)
2
>>> factorial(15)
1307674368000L
]]> By: Scott Lamb http://peadrop.com/blog/2007/06/18/pickle-an-interesting-stack-language/#comment-149 Scott Lamb Tue, 19 Jun 2007 04:40:38 +0000 http://peadrop.com/blog/2007/06/18/pickle-an-interesting-stack-language/#comment-149 <p>Very timely. I was just thinking that a streaming unpickler would be necessary to make <a href="http://repo.or.cz/w/fast-export.git?a=blob;f=git-p4;h=2040591383e93db3544b50a118f8151062591d3d;hb=82f6aacdb7fc1cc4baf9e46bed471f61177066d5" rel="nofollow">git-p4</a>'s readP4Files not require crazy amounts of memory, and here you've described the format. Bookmarked.</p> Very timely. I was just thinking that a streaming unpickler would be necessary to make git-p4’s readP4Files not require crazy amounts of memory, and here you’ve described the format. Bookmarked.

]]> By: grzywacz http://peadrop.com/blog/2007/06/18/pickle-an-interesting-stack-language/#comment-150 grzywacz Tue, 19 Jun 2007 00:11:56 +0000 http://peadrop.com/blog/2007/06/18/pickle-an-interesting-stack-language/#comment-150 <p>A very nice post indeed. Thanks for sharing your knowledge. :)</p> A very nice post indeed. Thanks for sharing your knowledge. :)

]]> By: Jesse http://peadrop.com/blog/2007/06/18/pickle-an-interesting-stack-language/#comment-151 Jesse Mon, 18 Jun 2007 23:46:32 +0000 http://peadrop.com/blog/2007/06/18/pickle-an-interesting-stack-language/#comment-151 <p>This is really fantastic!</p> This is really fantastic!

]]> By: Simon http://peadrop.com/blog/2007/06/18/pickle-an-interesting-stack-language/#comment-153 Simon Mon, 18 Jun 2007 20:13:29 +0000 http://peadrop.com/blog/2007/06/18/pickle-an-interesting-stack-language/#comment-153 <p>Fun!</p> <p>This is exactly the kind of post I like to read.</p> Fun!

This is exactly the kind of post I like to read.

]]> By: Brett http://peadrop.com/blog/2007/06/18/pickle-an-interesting-stack-language/#comment-152 Brett Mon, 18 Jun 2007 19:17:58 +0000 http://peadrop.com/blog/2007/06/18/pickle-an-interesting-stack-language/#comment-152 <p>Nice post! I had never bothered to look at how pickle worked. It also now makes more sense why pickle exists on top of there also being marshal.</p> Nice post! I had never bothered to look at how pickle worked. It also now makes more sense why pickle exists on top of there also being marshal.

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