doy/parse-keyword

DEPRECATED: write syntax extensions in perl

parse-keyword's Issues

Feature request - the ability to set sub attributes on returned coderefs

It would be nice if the parse_* functions accepted a second parameter allowing subroutine attributes (such as :lvalue) to be set for the coderef that gets returned.

While some subroutine attributes can be set via attributes.pm at run-time, some attributes (such as :lvalue) need to be set while the CV is being built, or else they don't work properly.

That is, ideally Parse::Keyword's parser_fn function should pass the subroutine attributes as the 4th (counting from 1, not 0) parameter to newATTRSUB.

I don't know how much work this request would represent, but it would really be handy for me. It strikes me as something that could be useful for the p5-mop method keyword too.

coderef returned by parse_fullexpr seems to always return the same thing

Given the following, the warning "GOT foo" is printed twice. I'd expect "GOT foo" and then "GOT bar". Am I doing something wrong?

use strict;
use warnings;

BEGIN {
    package PerlX::Switch;
    $INC{'PerlX/Switch.pm'} = __FILE__;

    use Exporter 'import';
    our @EXPORT = qw( switch );

    use Parse::Keyword { switch => \&_parse_switch };

    use match::simple qw( match );

    sub switch
    {
        my ($expr, $cases, $default) = @_;

        local $_ = $expr->();
        warn "GOT $_";

        CASE: for my $case ( @$cases )
        {
            my ($type, $condition, $block) = @$case;

            my $matched = 0;
            if ($type eq 'block')
            {
                $matched = !!$condition->();
            }
            else
            {
                my @terms = $condition->();
                TERM: for my $term (@terms)
                {
                    match($_, $term) ? (++$matched && last TERM) : next TERM;
                }
            }

            return $block->() if $matched;
        }

        return $default->() if $default;
        return;
    }

    sub _parse_switch
    {
        my ($expr);

        lex_read_space;
        die "syntax error; expected open parenthesis" unless lex_peek eq '(';
        lex_read(1);
        lex_read_space;

        $expr = parse_fullexpr;

        lex_read_space;
        die "syntax error; expected close parenthesis" unless lex_peek eq ')';
        lex_read(1);
        lex_read_space;

        die "syntax error; expected block" unless lex_peek eq '{';
        lex_read(1);
        lex_read_space;

        my @cases;
        while ( lex_peek(4) eq 'case' )
        {
            lex_read(4);
            push @cases, _parse_case();
            lex_read_space;
        }

        my $default;
        if ( lex_peek(4) eq 'else' )
        {
            lex_read(4);
            lex_read_space;
            $default = _parse_consequence();
            lex_read_space;
        }

        die "syntax error; expected end of switch block" unless lex_peek eq '}';
        lex_read(1);

        return (
            sub { ($expr, \@cases, $default) },
            1,
        );
    }

    sub _parse_case
    {
        my ($expr, $type);
        lex_read_space;

        if (lex_peek eq '(')
        {
            lex_read(1);
            $type = 'term';
            $expr = parse_fullexpr;
            lex_read_space;
            die "syntax error; expected close parenthesis" unless lex_peek eq ')';
            lex_read(1);
            lex_read_space;
        }

        elsif (lex_peek eq '{')
        {
            $type = 'block';
            $expr = parse_block;
            lex_read_space;
        }

        else
        {
            $type = 'simple-term';
            $expr = parse_fullexpr;
            lex_read_space;
        }

        my $block = _parse_consequence();       
        return [ $type, $expr, $block ];
    }

    sub _parse_consequence
    {
        my ($expr, $type);
        lex_read_space;

        my $block;
        if (lex_peek eq ':')
        {
            lex_read(1);
            lex_read_space;
            $block = parse_fullexpr;
            lex_read_space;
            die "syntax error; expected semicolon" unless lex_peek eq ';' || lex_peek eq '}';
            lex_read(1) && lex_read_space while lex_peek eq ';';
        }
        else
        {
            $block = parse_block;
            lex_read_space;
            lex_read(1) && lex_read_space while lex_peek eq ';';
        }

        return $block;
    }
};

use v5.14;
use PerlX::Switch;

sub xyz
{
    my $var = shift;
    switch ( $var ) {
        case "foo":          3;
        case ("bar")         { say "here";  1 }
        case { $_ eq "baz" } { say "there"; 2 }
        else                 { say "everywhere"; 99 }
    }
}

xyz("foo");
xyz("bar");

Failure when used on expression level

When using Parse::Keyword on the expression level, the custom parser runs as expected. However, a nondescriptive syntax error is thrown afterwards. Code to reproduce:

# tested under perl 5.18.1
BEGIN {
  use Parse::Keyword {
    foo => sub {
      warn "parser runs all right";
      return sub { 42 }, 1;
    },
  };
  sub foo { print @_, "\n" }
}

#1. this works fine:
foo;

#2. this fails:
my $x = foo;

#3. but this works, of course:
my $y = do { foo };

The error message in the 2nd case is:

syntax error at - line 16, near "= foo"
Execution of - aborted due to compilation errors.

Can this error be avoided?

If not, can a better error message be displayed when Parse::Keyword is used on the expression level? Adding this to the “Limitations” section of the documentation might be helpful as well.

Does not appear to work in conjunction with Exporter::Lexical

As per my previous issue, parsed keywords do need to be exported. However, exporting them as lexical subs does not seem to be sufficient; they seem to need to be exported into the compiling package.

doesn't work on lexical subs

Related to https://rt.cpan.org/Ticket/Display.html?id=89370.

Test suite fails with bleadperl (5.21.4) due to changed error message

With perl 5.21.4 the error.t test fails:

#   Failed test at t/error.t line 62.
#          got: 'Global symbol "$baz" requires explicit package name (did you forget to declare "my $baz"?) at t/error.pl line 9.
# Execution of t/error.pl aborted due to compilation errors.
# '                       
#     expected: 'Global symbol "$baz" requires explicit package name at t/error.pl line 9.
# Execution of t/error.pl aborted due to compilation errors.
# '                       
# Looks like you failed 1 test of 21.
t/error.t .....................
Dubious, test returned 1 (wstat 256, 0x100)
Failed 1/21 subtests      

SYNOPSIS should include exporting the "try" function

It should include something like:

use Exporter 'import';
our @EXPORT = qw(try);

Travis builds on Perl 5.19 fail

See here https://travis-ci.org/doy/parse-keyword/jobs/59163143

Looks like it can't find dzil...

t/fun/name.t fails

I assume this is related to my locale, note the "" instead of the tested '' around the abc in the second line or the error:

#   Failed test at t/fun/name.t line 32.
#                   'abc 123 at t/fun/name.t line 22.
#       Foo::foo("abc", 123) called at t/fun/name.t line 26
#       eval {...} called at t/fun/name.t line 25
# '
#     doesn't match '(?^:^abc 123 at t/fun/name.t line 22\.?\n\tFoo::foo\('abc', 123\) called at t/fun/name.t line 26)'
# Looks like you failed 1 test of 2.
t/fun/name.t ..................
Dubious, test returned 1 (wstat 256, 0x100)
Failed 1/2 subtests

brewed Perl 5.18.1 -Duserelocatableinc -Dusethreads

[ahartmai@ahartmai-nb:~/perl5/git/p5-mop-redux$ (master)]$ env | grep LC
LC_PAPER=de_AT.UTF-8
LC_ADDRESS=de_AT.UTF-8
LC_MONETARY=de_AT.UTF-8
LC_NUMERIC=de_AT.UTF-8
LC_TELEPHONE=de_AT.UTF-8
LC_IDENTIFICATION=de_AT.UTF-8
LC_MEASUREMENT=de_AT.UTF-8
LC_TIME=de_AT.UTF-8
LC_NAME=de_AT.UTF-8

install fails on windows

cpanm (App::cpanminus) 1.6005 on perl 5.016003 built for MSWin32-x64-multi-thread
You have make C:\strawberry5.16\c\bin\dmake.exe
You have LWP 6.04
You have "C:\Program Files (x86)\Git\bin\tar.exe", "C:\Program Files (x86)\Git\bin\gzip.exe" and "C:\Program Files (x86)\Git\bin\bzip2.exe"
You have "C:\Program Files (x86)\Git\bin\unzip.exe"
Searching Parse::Keyword on cpanmetadb ...
--> Working on Parse::Keyword
Fetching http://www.cpan.org/authors/id/D/DO/DOY/Parse-Keyword-0.05.tar.gz
-> OK
Unpacking Parse-Keyword-0.05.tar.gz
Entering Parse-Keyword-0.05
Checking configure dependencies from META.json
Checking if you have ExtUtils::MakeMaker 6.30 ... Yes (6.64)
Checking if you have Devel::CallParser 0 ... Yes (0.001)
Configuring Parse-Keyword-0.05
Running Makefile.PL
Checking if your kit is complete...
Looks good
Writing Makefile for Parse::Keyword
Writing MYMETA.yml and MYMETA.json
-> OK
Checking dependencies from MYMETA.json ...
Checking if you have Test::More 0.88 ... Yes (0.98)
Checking if you have File::Find 0 ... Yes (1.20)
Checking if you have File::Temp 0 ... Yes (0.22)
Checking if you have Exporter 0 ... Yes (5.67)
Checking if you have if 0 ... Yes (0.0602)
Checking if you have Carp 0 ... Yes (1.26)
Checking if you have Test::More 0.88 ... Yes (0.98)
Checking if you have File::Find 0 ... Yes (1.20)
Checking if you have File::Temp 0 ... Yes (0.22)
Checking if you have Exporter 0 ... Yes (5.67)
Checking if you have if 0 ... Yes (0.0602)
Checking if you have Carp 0 ... Yes (1.26)
Checking if you have warnings 0 ... Yes (1.13)
Checking if you have strict 0 ... Yes (1.07)
Checking if you have XSLoader 0 ... Yes (0.16)
Checking if you have Devel::CallParser 0 ... Yes (0.001)
Building and testing Parse-Keyword-0.05
cp lib/Parse/Keyword.pm blib\lib\Parse\Keyword.pm
C:\strawberry5.16\perl\bin\perl.exe C:\strawberry5.16\perl\lib\ExtUtils\xsubpp  -typemap C:\strawberry5.16\perl\lib\ExtUtils\typemap  Keyword.xs > Keyword.xsc && C:\strawberry5.16\perl\bin\perl.exe -MExtUtils::Command -e mv -- Keyword.xsc Keyword.c
gcc -c      -s -O2 -DWIN32 -DWIN64 -DCONSERVATIVE -DPERL_TEXTMODE_SCRIPTS -DPERL_IMPLICIT_CONTEXT -DPERL_IMPLICIT_SYS -fno-strict-aliasing -mms-bitfields -s -O2      -DVERSION=\"0.05\"    -DXS_VERSION=\"0.05\"  "-IC:\strawberry5.16\perl\lib\CORE"   Keyword.c
Running Mkbootstrap for Parse::Keyword ()
C:\strawberry5.16\perl\bin\perl.exe -MExtUtils::Command -e chmod -- 644 Keyword.bs
C:\strawberry5.16\perl\bin\perl.exe -MExtUtils::Mksymlists \
     -e "Mksymlists('NAME'=>\"Parse::Keyword\", 'DLBASE' => 'Keyword', 'DL_FUNCS' => {  }, 'FUNCLIST' => [], 'IMPORTS' => {  }, 'DL_VARS' => []);"
dlltool --def Keyword.def --output-exp dll.exp
g++ -o blib\arch\auto\Parse\Keyword\Keyword.dll -Wl,--base-file -Wl,dll.base -mdll -s -L"C:\strawberry5.16\perl\lib\CORE" -L"C:\strawberry5.16\c\lib" Keyword.o   C:\strawberry5.16\perl\lib\CORE\libperl516.a -lmoldname -lkernel32 -luser32 -lgdi32 -lwinspool -lcomdlg32 -ladvapi32 -lshell32 -lole32 -loleaut32 -lnetapi32 -luuid -lws2_32 -lmpr -lwinmm -lversion -lodbc32 -lodbccp32 -lcomctl32 dll.exp
Keyword.o:Keyword.c:(.text+0x16b3): undefined reference to `__imp_C8K61oRQKxigiqmUlVdk_scp1'
Keyword.o:Keyword.c:(.text+0x1836): undefined reference to `__imp_Perl_scalar'
c:/strawberry5.16/c/bin/../lib/gcc/x86_64-w64-mingw32/4.6.3/../../../../x86_64-w64-mingw32/bin/ld.exe: Keyword.o: bad reloc address 0x0 in section `.pdata'
c:/strawberry5.16/c/bin/../lib/gcc/x86_64-w64-mingw32/4.6.3/../../../../x86_64-w64-mingw32/bin/ld.exe: final link failed: Invalid operation
collect2: ld returned 1 exit status
dmake.exe:  Error code 129, while making 'blib\arch\auto\Parse\Keyword\Keyword.dll'
-> FAIL Installing Parse::Keyword failed. See C:\Users\Andre\.cpanm\build.log for details.