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1 Path: cwi.nl!sun4nl!mcsun!uunet!cs.utexas.edu!convex!usenet |
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2 From: tchrist@convex.COM (Tom Christiansen) |
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3 Newsgroups: comp.lang.perl |
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4 Subject: Re: The problems of Perl (Re: Question (silly?)) |
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5 Message-ID: <1992Jan17.053115.4220@convex.com> |
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6 Date: 17 Jan 92 05:31:15 GMT |
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7 References: <17458@ector.cs.purdue.edu> <1992Jan16.165347.25583@cherokee.uswest.com> <=#Hues+4@cs.psu.edu> |
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8 Sender: usenet@convex.com (news access account) |
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9 Reply-To: tchrist@convex.COM (Tom Christiansen) |
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10 Organization: CONVEX Realtime Development, Colorado Springs, CO |
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11 Lines: 83 |
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12 Nntp-Posting-Host: pixel.convex.com |
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13 |
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14 From the keyboard of flee@cs.psu.edu (Felix Lee): |
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15 :And Perl is definitely awkward with data types. I haven't yet found a |
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16 :pleasant way of shoving non-trivial data types into Perl's grammar. |
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17 |
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18 Yes, it's pretty aweful at that, alright. Sometimes I write perl programs |
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19 that need them, and sometimes it just takes a little creativity. But |
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20 sometimes it's not worth it. I actually wrote a C program the other day |
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21 (gasp) because I didn't want to deal with a game matrix with six links per node. |
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22 |
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23 :Here's a very simple problem that's tricky to express in Perl: process |
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24 :the output of "du" to produce output that's indented to reflect the |
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25 :tree structure, and with each subtree sorted by size. Something like: |
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26 : 434 /etc |
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27 : | 344 . |
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28 : | 50 install |
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29 : | 35 uucp |
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30 : | 3 nserve |
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31 : | | 2 . |
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32 : | | 1 auth.info |
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33 : | 1 sm |
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34 : | 1 sm.bak |
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35 |
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36 At first I thought I could just keep one local list around |
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37 at once, but this seems inherently recursive. Which means |
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38 I need an real recursive data structure. Maybe you could |
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39 do it with one of the %assoc arrays Larry uses in the begat |
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40 programs, but I broke down and got dirty. I think the hardest |
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41 part was matching Felix's desired output exactly. It's not |
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42 blazingly fast: I should probably inline the &childof routine, |
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43 but it *was* faster to write than I could have written the |
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44 equivalent C program. |
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45 |
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46 |
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47 --tom |
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48 |
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49 -- |
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50 "GUIs normally make it simple to accomplish simple actions and impossible |
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51 to accomplish complex actions." --Doug Gwyn (22/Jun/91 in comp.unix.wizards) |
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52 |
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53 Tom Christiansen tchrist@convex.com convex!tchrist |
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54 |