Re: The semicolon habit (was: Q: Definition

Mark Lutz (lutz@KaPRE.COM) wrote:
: Charles Fiterman <cef@geodesic.com> writes:
: >[use indentation to show block structure]


: I caught this discussion late, so forgive me if this has already
: been mentioned. But if you're interested in seeing an example
: of a language where blocks are based on indentation, and lines
: don't need explicit terminators, have a look at Python, a newer
: object-oriented scripting/extension language.


I also caught this discussion late, but the idea of using indentation to
describe the layout or programs, has been used well in functional languages
for a number of years. Further more the modern functional language Haskell
allows the programmer to mix both {} and semi-colon's to describe layout
or use what is know as the offside rule (originally proposed by Landin).


The offside rule allows the braces and semi-colons to implicit instead of
emplicit, through the use of indentation. For more details (including a full
specification of the offside rule used in Haskell) see the Haskell 1.2
report:


@ARTICLE{hudak,
      AUTHOR = "P. Hudak and S. Peyton Jones and P. Walder (editors)",
      TITLE = "Report on the Programming Language Haskell. A Non-strict Pure
ly Functional Language (Version 1.2)",
      JOURNAL = "ACM SIGPLAN Notices",
      VOLUME = 27,
      NUMBER = 5,
      YEAR = "May 1992"}


anonymous ftp ::: ftp.cs.nott.ac.uk
/pub/haskell/report/report-1.2.ps.Z


Ben.
--
Benedict R. Gaster
Nottingham Trent University
sys3bga@doc.ntu.ac.uk
--

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