Article View: comp.lang.misc
Article #1489Re: He's not the only one at it again!
From: David Gudeman
Date: Sat, 11 Aug 1990 22:10
Date: Sat, 11 Aug 1990 22:10
32 lines
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1954 bytes
In article <27159@nigel.ee.udel.edu> carroll@udel.edu (Mark Carroll <MC>) writes: =In article <675@garth.UUCP> smryan@garth.UUCP (sous-realiste) writes: =]]_not_ a feature of our programs. If I declare =]] var x: 12223495872309457 .. 2345230549872039458720983475; =]]then any compiler worth its salt ought to be able to figure out how many =]]of its nasty little boxes to use, and how to exploit whatever instructions =]. . . =] =]Do you have any idea what this does to the context sensitive grammar of =]the language? = =This seems to be nothing more than Pascal like subranges combined with =Lisp-like bignums. Lisp does not include the type system in the grammar. All values in Lisp have to carry their type around with them, and all operations have to check the type at run time to make sure the operation is legal. This slows things down. Pascal, C and similar languages fix the types of variables and other expressions at compile time. I don't agree with the original author that this is a problem though. Given different lengths of integers, operations can be defined to produce an int of length equal to the length of the longest operand. Given subranges of the sort described, the result of an operation should be an integer of the same length as the longest subrange, with no range restrictions. The range restrictions are checked when assigning to a variable that has a restricted range. -- David Gudeman Department of Computer Science The University of Arizona gudeman@cs.arizona.edu Tucson, AZ 85721 noao!arizona!gudeman
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Path: arc1-ca.pugleaf.net!utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!mailrus!ncar!noao!arizona!gudeman From: gudeman@cs.arizona.edu (David Gudeman) Newsgroups: comp.lang.misc Subject: Re: He's not the only one at it again! Message-ID: <24153@megaron.cs.arizona.edu> Date: 11 Aug 90 22:10:51 GMT Organization: U of Arizona CS Dept, Tucson Lines: 32