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a653024ab7
If we want to encourage people to read the sample programs
and learn Mercury programming from them, they should not be written
in an obsolete style.
samples/beer.m:
samples/calculator.m:
samples/calculator2.m:
samples/concurrency/midimon/midimon.m:
samples/diff/diff_out.m:
samples/e.m:
samples/eliza.m:
samples/muz/dict.m:
samples/muz/higher_order.m:
samples/muz/muz.m:
samples/muz/typecheck.m:
samples/muz/word.m:
samples/muz/zabstract.m:
samples/muz/zlogic.m:
samples/muz/zparser.m:
samples/muz/ztoken.m:
samples/muz/ztoken_io.m:
samples/muz/ztype.m:
samples/muz/ztype_op.m:
samples/rot13/rot13_concise.m:
samples/rot13/rot13_gustavo.m:
samples/rot13/rot13_juergen.m:
samples/rot13/rot13_ralph.m:
samples/rot13/rot13_verbose.m:
samples/solutions/all_solutions.m:
samples/solutions/n_solutions.m:
samples/solutions/one_solution.m:
samples/solutions/some_solutions.m:
samples/solver_types/eqneq.m:
samples/solver_types/sudoku.m:
samples/solver_types/test_eqneq.m:
Replace uses of __ as module qualifier with dot.
Replace (C->T;E) with (if C then T else E).
Use our usual indentation for if-then-elses and for switches.
Import one module per line. Put those imports into alphabetical order.
Replace many uses of DCGs with state variables, leaving DCGs
mostly just for parsing code.
Use predmode declarations where this helps.
Put predicates in top-down order where relevant.
Use io.format where this helps.
Do not put more than one predicate call on one line.
Put each function symbol in a du type on a separate line.
Put spaces after commas, around the bar in list syntax,
around arithmetic operators, and around minus signs used for pairs.
Replace tab indentation with four-space indentation.
Delete spaces at the ends of lines.
Replace two or more consecutive blank lines with one blank line.
Delete blank lines that do not help structure the code.
There are probably still some examples of old practices remaining;
I do not claim to have fixed them all.
66 lines
1.5 KiB
Mathematica
66 lines
1.5 KiB
Mathematica
%---------------------------------------------------------------------------%
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% vim: ft=mercury ts=4 sw=4 et
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%---------------------------------------------------------------------------%
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%
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% file: beer.m
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% author:
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% Fergus Henderson <fjh@cs.mu.oz.au> Thursday 9th November 1995
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% Re-written with new syntax standard library calls:
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% Paul Bone <paul@mercurylang.org> 2015-11-20
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%
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% This beer song is more idiomatic Mercury than the original, I feel bad
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% saying that since Fergus is a founder of the language.
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:- module beer.
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:- interface.
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:- import_module io.
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:- pred main(io::di, io::uo) is det.
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:- implementation.
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:- import_module int.
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:- import_module list.
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:- import_module string.
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main(!IO) :-
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beer(99, !IO).
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:- pred beer(int::in, io::di, io::uo) is det.
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beer(N, !IO) :-
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io.write_string(beer_stanza(N), !IO),
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( if N > 0 then
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io.nl(!IO),
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beer(N - 1, !IO)
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else
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true
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).
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:- func beer_stanza(int) = string.
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beer_stanza(N) = Stanza :-
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( if N = 0 then
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Stanza = "Go to the store and buy some more!\n"
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else
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NBottles = bottles_line(N),
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N1Bottles = bottles_line(N - 1),
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Stanza =
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NBottles ++ " on the wall.\n" ++
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NBottles ++ ".\n" ++
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"Take one down, pass it around,\n" ++
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N1Bottles ++ " on the wall.\n"
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).
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:- func bottles_line(int) = string.
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bottles_line(N) =
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( if N = 0 then
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"No more bottles of beer"
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else if N = 1 then
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"1 bottle of beer"
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else
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string.format("%d bottles of beer", [i(N)])
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).
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