300 lines
8.1 KiB
Markdown
300 lines
8.1 KiB
Markdown
---
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created_at: '2014-08-23T03:45:38.000Z'
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title: BASIC as a Haskell DSL (2009)
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url: http://augustss.blogspot.com/search/label/BASIC
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author: tel
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points: 58
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story_text: ''
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comment_text:
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num_comments: 12
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story_id:
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story_title:
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story_url:
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parent_id:
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created_at_i: 1408765538
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_tags:
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- story
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- author_tel
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- story_8214927
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objectID: '8214927'
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year: 2009
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---
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[Source](http://augustss.blogspot.com/search/label/BASIC "Permalink to Things that amuse me")
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# Things that amuse me
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# Things that amuse me
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## Saturday, February 07, 2009
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## More BASIC
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Not that anybody should care, but I've reimplemented by BASIC.
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Here's a simple program.
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{-# LANGUAGE ExtendedDefaultRules, OverloadedStrings #-}
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import BASIC
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main = runBASIC $ do
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10 GOSUB 1000
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20 PRINT "* Welcome to HiLo *"
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30 GOSUB 1000
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100 LET I := INT(100 * RND(0))
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200 PRINT "Guess my number:"
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210 INPUT X
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220 LET S := SGN(I-X)
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230 IF S <> 0 THEN 300
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240 FOR X := 1 TO 5
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250 PRINT X*X;" You won!"
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260 NEXT X
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270 STOP
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300 IF S <> 1 THEN 400
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310 PRINT "Your guess ";X;" is too low."
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320 GOTO 200
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400 PRINT "Your guess ";X;" is too high."
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410 GOTO 200
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1000 PRINT "*******************"
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1010 RETURN
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9999 END
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In some ways this is a step backwards, since it requires some language extensions in Main. But I wanted to be able to use semicolon in the print statement.
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But there it is, an exciting game!
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*******************
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* Welcome to HiLo *
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*******************
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Guess my number:
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50
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Your guess 50 is too high.
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Guess my number:
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25
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Your guess 25 is too low.
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Guess my number:
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37
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Your guess 37 is too low.
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Guess my number:
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44
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Your guess 44 is too low.
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Guess my number:
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47
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Your guess 47 is too low.
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Guess my number:
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48
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1 You won!
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4 You won!
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9 You won!
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16 You won!
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25 You won!
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Labels: [BASIC][1], [DSL][2], [Haskell][3]
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_posted by augustss at [8:31 PM][4]_ [8 comments][5] ![][6]
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## Friday, February 06, 2009
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## Is Haskell fast?
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Let's do a simple benchmark comparing Haskell to C. My benchmark computes an approximation to infinity by adding up 1/n. Here is the C code:
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#include <stdio.h>
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int
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main(int argc, char **argv)
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{
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double i, s;
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s = 0;
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for (i = 1; i < 100000000; i++)
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s += 1/i;
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printf("Almost infinity is %gn", s);
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}
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And running it
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Lennarts-Computer% gcc -O3 inf.c -o inf
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Lennarts-Computer% time ./inf
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Almost infinity is 18.9979
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1.585u 0.009s 0:01.62 97.5% 0+0k 0+0io 0pf+0w
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And now the Haskell code:
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import BASIC
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main = runBASIC' $ do
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10 LET I =: 1
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20 LET S =: 0
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30 LET S =: S + 1/I
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40 LET I =: I + 1
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50 IF I <> 100000000 THEN 30
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60 PRINT "Almost infinity is"
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70 PRINT S
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80 END
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And running it:
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Lennarts-Computer% ghc --make Main.hs
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[4 of 4] Compiling Main ( Main.hs, Main.o )
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Linking Main ...
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Lennarts-Computer% ./Main
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Almost infinity is
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18.9979
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CPU time: 1.57s
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As you can see it's about the same time. In fact the assembly code for the loops look pretty much the same. Here's the Haskell one:
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LBB1_1: ## _L4
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movsd LCPI1_0, %xmm2
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movapd %xmm1, %xmm3
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addsd %xmm2, %xmm3
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ucomisd LCPI1_1, %xmm3
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divsd %xmm1, %xmm2
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addsd %xmm2, %xmm0
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movapd %xmm3, %xmm1
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jne LBB1_1 ## _L4
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Labels: [BASIC][1], [Benchmark][7], [DSL][2], [Haskell][3], [LLVM][8]
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_posted by augustss at [4:50 PM][9]_ [11 comments][10] ![][6]
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## Regression
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They say that as you get older you regress back towards childhood. So I present you with today's Haskell program (the idea shamelessly stolen from JoshTriplett from #haskell on IRC):
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import BASIC
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main = runBASIC $ do
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10 LET X =: 1
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20 PRINT "Hello BASIC world!"
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30 LET X =: X + 1
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40 IF X <> 11 THEN 20
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50 END
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Yes, it runs. (I'm sorry about the `=:` instead of `=`, but some things are just too wired into Haskell to change.)
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Labels: [BASIC][1], [DSL][2], [Haskell][3]
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_posted by augustss at [11:12 AM][11]_ [13 comments][12] ![][6]
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## About Me
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: **Name:** [ augustss ][13]
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: **Location:** London, United Kingdom
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[View my complete profile][13]
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## Links
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* [Google News][14]
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* [Jessica][15]
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## Previous Posts
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* [A commentary on 24 days of GHC extensions, part 3][16]
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* [A commentary on 24 days of GHC extensions, part 2][17]
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* [A commentary on 24 days of GHC extensions][18]
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* [Haskell error reporting with locations, update][19]
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* [Haskell error reporting with locations][20]
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* [A small Haskell extension][21]
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* [ Impredicative polymorphism, a use case In a recen...][22]
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* [ More points for lazy evaluation In a recent blo...][23]
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* [ Ugly memoization Here's a problem that I recentl...][24]
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* [Phew! Cleaned out a lot of spam comments in my bl...][25]
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## Archives
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* [April 2007][26]
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* [May 2007][27]
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* [June 2007][28]
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* [July 2007][29]
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* [August 2007][30]
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* [October 2007][31]
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* [November 2007][32]
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* [March 2008][33]
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* [July 2008][34]
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* [December 2008][35]
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* [January 2009][36]
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* [February 2009][37]
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* [June 2009][38]
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* [April 2011][39]
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* [May 2011][40]
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* [July 2011][41]
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* [April 2014][42]
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* [December 2014][43]
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![Powered by Blogger][44]
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* * *
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[1]: http://augustss.blogspot.com/search/label/BASIC
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[2]: http://augustss.blogspot.com/search/label/DSL
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[3]: http://augustss.blogspot.com/search/label/Haskell
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[4]: http://augustss.blogspot.com/2009/02/more-basic-not-that-anybody-should-care.html "permanent link"
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[5]: https://www.blogger.com/comment.g?blogID=25541020&postID=3941171818143196666
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[6]: https://img2.blogblog.com/img/icon18_edit_allbkg.gif
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[7]: http://augustss.blogspot.com/search/label/Benchmark
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[8]: http://augustss.blogspot.com/search/label/LLVM
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[9]: http://augustss.blogspot.com/2009/02/is-haskell-fast-lets-do-simple.html "permanent link"
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[10]: https://www.blogger.com/comment.g?blogID=25541020&postID=5253528735726768410
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[11]: http://augustss.blogspot.com/2009/02/regression-they-say-that-as-you-get.html "permanent link"
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[12]: https://www.blogger.com/comment.g?blogID=25541020&postID=7024343775777574640
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[13]: https://www.blogger.com/profile/07327620522294658036
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[14]: http://news.google.com/
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[15]: http://jes6ica.blogspot.com/
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[16]: http://augustss.blogspot.com/2014/12/its-time-for-some-more-haskell-opinions.html
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[17]: http://augustss.blogspot.com/2014/12/a-commentary-on-24-days-of-ghc_19.html
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[18]: http://augustss.blogspot.com/2014/12/a-commentary-on-24-days-of-ghc.html
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[19]: http://augustss.blogspot.com/2014/04/haskell-error-reporting-with-locations_5.html
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[20]: http://augustss.blogspot.com/2014/04/haskell-error-reporting-with-locations.html
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[21]: http://augustss.blogspot.com/2014/04/a-small-haskell-extension.html
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[22]: http://augustss.blogspot.com/2011/07/impredicative-polymorphism-use-case-in.html
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[23]: http://augustss.blogspot.com/2011/05/more-points-for-lazy-evaluation-in.html
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[24]: http://augustss.blogspot.com/2011/04/ugly-memoization-heres-problem-that-i.html
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[25]: http://augustss.blogspot.com/2011/04/phew-cleaned-out-lot-of-spam-comments.html
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[26]: http://augustss.blogspot.com/2007/04/
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[27]: http://augustss.blogspot.com/2007/05/
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[28]: http://augustss.blogspot.com/2007/06/
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[29]: http://augustss.blogspot.com/2007/07/
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[30]: http://augustss.blogspot.com/2007/08/
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[31]: http://augustss.blogspot.com/2007/10/
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[32]: http://augustss.blogspot.com/2007/11/
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[33]: http://augustss.blogspot.com/2008/03/
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[34]: http://augustss.blogspot.com/2008/07/
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[35]: http://augustss.blogspot.com/2008/12/
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[36]: http://augustss.blogspot.com/2009/01/
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[37]: http://augustss.blogspot.com/2009/02/
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[38]: http://augustss.blogspot.com/2009/06/
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[39]: http://augustss.blogspot.com/2011/04/
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[40]: http://augustss.blogspot.com/2011/05/
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[41]: http://augustss.blogspot.com/2011/07/
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[42]: http://augustss.blogspot.com/2014/04/
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[43]: http://augustss.blogspot.com/2014/12/
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[44]: http://buttons.blogger.com/bloggerbutton1.gif
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