sort mygrep {1} keys %hash ...will not compile #15304

p5pRT · 2016-05-02T21:41:04Z

Migrated from rt.perl.org#128057 (status was 'rejected')

Searchable as RT128057$

p5pRT · 2016-05-02T21:41:04Z

From @jimav

This is a bug report for perl from jim.avera@gmail.com,
generated with the help of perlbug 1.40 running under perl 5.20.2.

sub mygrep (&@) { }

my @b = sort grep {1} keys %ENV; # works
my @a = mygrep {1} keys %ENV; # works
my @c = sort mygrep {1}, keys %ENV; # works
my @d = sort mygrep {1} keys %ENV; # syntax error "} keys"

Flags:
category=core
severity=low

Site configuration information for perl 5.20.2:

Configured by Debian Project at Tue Mar 1 16:51:39 UTC 2016.

Summary of my perl5 (revision 5 version 20 subversion 2) configuration:

Platform:
osname=linux, osvers=3.13.0-79-generic, archname=x86_64-linux-gnu-thread-multi
uname='linux lgw01-20 3.13.0-79-generic #123-ubuntu smp fri feb 19 14:27:58 utc 2016 x86_64 x86_64 x86_64 gnulinux '
config_args='-Dusethreads -Duselargefiles -Dccflags=-DDEBIAN -D_FORTIFY_SOURCE=2 -g -O2 -fstack-protector-strong -Wformat -Werror=format-security -Dldflags= -Wl,-Bsymbolic-functions -Wl,-z,relro -Dlddlflags=-shared -Wl,-Bsymbolic-functions -Wl,-z,relro -Dcccdlflags=-fPIC -Darchname=x86_64-linux-gnu -Dprefix=/usr -Dprivlib=/usr/share/perl/5.20 -Darchlib=/usr/lib/x86_64-linux-gnu/perl/5.20 -Dvendorprefix=/usr -Dvendorlib=/usr/share/perl5 -Dvendorarch=/usr/lib/x86_64-linux-gnu/perl5/5.20 -Dsiteprefix=/usr/local -Dsitelib=/usr/local/share/perl/5.20.2 -Dsitearch=/usr/local/lib/x86_64-linux-gnu/perl/5.20.2 -Dman1dir=/usr/share/man/man1 -Dman3dir=/usr/share/man/man3 -Dsiteman1dir=/usr/local/man/man1 -Dsiteman3dir=/usr/local/man/man3 -Duse64bitint -Dman1ext=1 -Dman3ext=3perl -Dpager=/usr/bin/sensible-pager -Uafs -Ud_csh -Ud_ualarm -Uusesfio -Uusenm -Ui_libutil -Uversiononly -DDEBUGGING=-g -Doptimize=-O2 -Duseshrplib -Dlibperl=libperl.so.5.20.2 -des'
hint=recommended, useposix=true, d_sigaction=define
useithreads=define, usemultiplicity=define
use64bitint=define, use64bitall=define, uselongdouble=undef
usemymalloc=n, bincompat5005=undef
Compiler:
cc='cc', ccflags ='-D_REENTRANT -D_GNU_SOURCE -DDEBIAN -fwrapv -fno-strict-aliasing -pipe -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64',
optimize='-O2 -g',
cppflags='-D_REENTRANT -D_GNU_SOURCE -DDEBIAN -fwrapv -fno-strict-aliasing -pipe -I/usr/local/include'
ccversion='', gccversion='5.2.1 20151010', gccosandvers=''
intsize=4, longsize=8, ptrsize=8, doublesize=8, byteorder=12345678
d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=16
ivtype='long', ivsize=8, nvtype='double', nvsize=8, Off_t='off_t', lseeksize=8
alignbytes=8, prototype=define
Linker and Libraries:
ld='cc', ldflags =' -fstack-protector -L/usr/local/lib'
libpth=/usr/local/lib /usr/lib/gcc/x86_64-linux-gnu/5/include-fixed /usr/include/x86_64-linux-gnu /usr/lib /lib/x86_64-linux-gnu /lib/../lib /usr/lib/x86_64-linux-gnu /usr/lib/../lib /lib
libs=-lgdbm -lgdbm_compat -ldb -ldl -lm -lpthread -lc -lcrypt
perllibs=-ldl -lm -lpthread -lc -lcrypt
libc=libc-2.21.so, so=so, useshrplib=true, libperl=libperl.so.5.20
gnulibc_version='2.21'
Dynamic Linking:
dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-Wl,-E'
cccdlflags='-fPIC', lddlflags='-shared -L/usr/local/lib -fstack-protector'

Locally applied patches:
DEBPKG:debian/cpan_definstalldirs - Provide a sensible INSTALLDIRS default for modules installed from CPAN.
DEBPKG:debian/db_file_ver - http://bugs.debian.org/340047 Remove overly restrictive DB_File version check.
DEBPKG:debian/doc_info - Replace generic man(1) instructions with Debian-specific information.
DEBPKG:debian/enc2xs_inc - http://bugs.debian.org/290336 Tweak enc2xs to follow symlinks and ignore missing @INC directories.
DEBPKG:debian/errno_ver - http://bugs.debian.org/343351 Remove Errno version check due to upgrade problems with long-running processes.
DEBPKG:debian/libperl_embed_doc - http://bugs.debian.org/186778 Note that libperl-dev package is required for embedded linking
DEBPKG:fixes/respect_umask - Respect umask during installation
DEBPKG:debian/writable_site_dirs - Set umask approproately for site install directories
DEBPKG:debian/extutils_set_libperl_path - EU:MM: set location of libperl.a under /usr/lib
DEBPKG:debian/no_packlist_perllocal - Don't install .packlist or perllocal.pod for perl or vendor
DEBPKG:debian/prefix_changes - Fiddle with *PREFIX and variables written to the makefile
DEBPKG:debian/fakeroot - Postpone LD_LIBRARY_PATH evaluation to the binary targets.
DEBPKG:debian/instmodsh_doc - Debian policy doesn't install .packlist files for core or vendor.
DEBPKG:debian/ld_run_path - Remove standard libs from LD_RUN_PATH as per Debian policy.
DEBPKG:debian/libnet_config_path - Set location of libnet.cfg to /etc/perl/Net as /usr may not be writable.
DEBPKG:debian/mod_paths - Tweak @INC ordering for Debian
DEBPKG:debian/module_build_man_extensions - http://bugs.debian.org/479460 Adjust Module::Build manual page extensions for the Debian Perl policy
DEBPKG:debian/prune_libs - http://bugs.debian.org/128355 Prune the list of libraries wanted to what we actually need.
DEBPKG:fixes/net_smtp_docs - [rt.cpan.org #36038] http://bugs.debian.org/100195 Document the Net::SMTP 'Port' option
DEBPKG:debian/perlivp - http://bugs.debian.org/510895 Make perlivp skip include directories in /usr/local
DEBPKG:debian/deprecate-with-apt - http://bugs.debian.org/747628 Point users to Debian packages of deprecated core modules
DEBPKG:debian/squelch-locale-warnings - http://bugs.debian.org/508764 Squelch locale warnings in Debian package maintainer scripts
DEBPKG:debian/skip-upstream-git-tests - Skip tests specific to the upstream Git repository
DEBPKG:debian/patchlevel - http://bugs.debian.org/567489 List packaged patches for 5.20.2-6ubuntu0.2 in patchlevel.h
DEBPKG:debian/skip-kfreebsd-crash - http://bugs.debian.org/628493 [perl #96272] Skip a crashing test case in t/op/threads.t on GNU/kFreeBSD
DEBPKG:fixes/document_makemaker_ccflags - http://bugs.debian.org/628522 [rt.cpan.org #68613] Document that CCFLAGS should include $Config{ccflags}
DEBPKG:debian/find_html2text - http://bugs.debian.org/640479 Configure CPAN::Distribution with correct name of html2text
DEBPKG:debian/perl5db-x-terminal-emulator.patch - http://bugs.debian.org/668490 Invoke x-terminal-emulator rather than xterm in perl5db.pl
DEBPKG:debian/cpan-missing-site-dirs - http://bugs.debian.org/688842 Fix CPAN::FirstTime defaults with nonexisting site dirs if a parent is writable
DEBPKG:fixes/memoize_storable_nstore - [rt.cpan.org #77790] http://bugs.debian.org/587650 Memoize::Storable: respect 'nstore' option not respected
DEBPKG:debian/regen-skip - Skip a regeneration check in unrelated git repositories
DEBPKG:fixes/regcomp-mips-optim - [perl #122817] http://bugs.debian.org/754054 Downgrade the optimization of regcomp.c on mips and mipsel due to a gcc-4.9 bug
DEBPKG:debian/makemaker-pasthru - http://bugs.debian.org/758471 Pass LD settings through to subdirectories
DEBPKG:fixes/perldoc-less-R - [rt.cpan.org #98636] http://bugs.debian.org/758689 Tell the 'less' pager to allow terminal escape sequences
DEBPKG:fixes/pod_man_reproducible_date - http://bugs.debian.org/759405 Support POD_MAN_DATE in Pod::Man for the left-hand footer
DEBPKG:fixes/io_uncompress_gunzip_inmemory - http://bugs.debian.org/747363 [rt.cpan.org #95494] Fix gunzip to in-memory file handle
DEBPKG:fixes/socket_test_recv_fix - http://bugs.debian.org/758718 [perl #122657] Compare recv return value to peername in socket test
DEBPKG:fixes/hurd_socket_recv_todo - http://bugs.debian.org/758718 [perl #122657] TODO checking the result of recv() on hurd
DEBPKG:fixes/regexp-performance - [0fa70a0] http://bugs.debian.org/777556 [perl #123743] simpify and speed up /.*.../ handling
DEBPKG:fixes/failed_require_diagnostics - http://bugs.debian.org/781120 [perl #123270] Report inaccesible file on failed require
DEBPKG:fixes/array-cloning - http://bugs.debian.org/779357 [perl #124127] [902d169] fix cloning arrays with unused elements
DEBPKG:fixes/perldb-threads - http://bugs.debian.org/779357 [perl #124127] [41ef2c6] lib/perl5db.pl: Restore noop lock prototype
DEBPKG:debian/locale-robustness - http://bugs.debian.org/782068 [perl #124310] Make t/run/locale.t survive missing locales masked by LC_ALL
DEBPKG:fixes/gcc5-errno - http://bugs.debian.org/778060 [perl #123784] [816b056] Fix Errno.pm generation for gcc-5.0
DEBPKG:fixes/h2ph-hex-constants - http://bugs.debian.org/778060 [perl #123784] [3bea78d] h2ph: correct handling of hex constants for the preamble
DEBPKG:fixes/h2ph-test-inc - http://bugs.debian.org/778060 [perl #123784] [3359391] lib/h2ph.t to test generated t/_h2ph_pre.ph instead of the system one
DEBPKG:fixes/podman-utc - http://bugs.debian.org/780259 Make the embedded date from Pod::Man reproducible
DEBPKG:fixes/podman-utc-docs - http://bugs.debian.org/780259 Documentation and test suite updates for UTC fix
DEBPKG:fixes/podman-empty-date - http://bugs.debian.org/780259 Support an empty POD_MAN_DATE environment variable
DEBPKG:fixes/podman-pipe - http://bugs.debian.org/777405 Better errors for man pages from standard input
DEBPKG:debian/pod2man-customized - Update porting/customized.dat for pod2man modifications
DEBPKG:fixes/CVE-2015-8607_file_spec_taint_fix - ensure File::Spec::canonpath() preserves taint
DEBPKG:fixes/CVE-2016-2381.patch - [PATCH 1/2] remove duplicate environment variables from environ

@INC for perl 5.20.2:
/home/jima/perl5/lib/perl5/x86_64-linux-gnu-thread-multi
/home/jima/perl5/lib/perl5
/home/jima/lib/perl
/etc/perl
/usr/local/lib/x86_64-linux-gnu/perl/5.20.2
/usr/local/share/perl/5.20.2
/usr/lib/x86_64-linux-gnu/perl5/5.20
/usr/share/perl5
/usr/lib/x86_64-linux-gnu/perl/5.20
/usr/share/perl/5.20
/usr/local/lib/site_perl
.

Environment for perl 5.20.2:
HOME=/home/jima
LANG=en_US.UTF-8
LANGUAGE=en_US
LD_LIBRARY_PATH (unset)
LOGDIR (unset)
PATH=/home/jima/perl5/bin:/home/jima/bin:/home/jima/jima_tools/x86_64/bin:/home/jima/jima_tools/bin:/opt/Adobe/Reader9/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/bin/X11:/usr/local/sbin:/usr/games:/usr/local/games:/usr/lib/jvm/java-8-oracle/bin:/usr/lib/jvm/java-8-oracle/db/bin:/usr/lib/jvm/java-8-oracle/jre/bin:.
PERL5LIB=/home/jima/perl5/lib/perl5:/home/jima/lib/perl
PERL_BADLANG (unset)
PERL_LOCAL_LIB_ROOT=/home/jima/perl5
PERL_MB_OPT=--install_base "/home/jima/perl5"
PERL_MM_OPT=INSTALL_BASE=/home/jima/perl5
SHELL=/bin/bash

p5pRT · 2016-05-02T22:03:02Z

From @cpansprout

On Mon May 02 14:41:04 2016, jim.avera@gmail.com wrote:

The sort operator has ‘extra special’ parsing rules.

sub mygrep (&@) { }

my @b = sort grep {1} keys %ENV; # works
my @a = mygrep {1} keys %ENV; # works
my @c = sort mygrep {1}, keys %ENV; # works

It compiles, but gives:

Sort subroutine didn't return single value at -e line 1.

because mygrep is the sort comparison routine, and {1}, keys %ENV (i.e., an anonymous hash, followed by the env var names) is the list of items to sort.

my @d = sort mygrep {1} keys %ENV; # syntax error "} keys"

Here, the list of items to sort is ({1} keys %ENV), which contains a syntax error.

Use +mygrep if you intend mygrep to be part of the source list. This is documented in perfunc:

Warning: syntactical care is required when sorting the list
returned from a function. If you want to sort the list returned by
the function call "find_records(@key)", you can use:

my @contact = sort { $a cmp $b } find_records @key;
my @contact = sort +find_records(@key);
my @contact = sort &find_records(@key);
my @contact = sort(find_records(@key));

If instead you want to sort the array @key with the comparison
routine "find_records()" then you can use:

my @contact = sort { find_records() } @key;
my @contact = sort find_records(@key);
my @contact = sort(find_records @key);
my @contact = sort(find_records (@key));

Not a bug.

--

Father Chrysostomos

p5pRT · 2016-05-02T22:03:02Z

The RT System itself - Status changed from 'new' to 'open'

p5pRT · 2016-05-02T22:03:02Z

@cpansprout - Status changed from 'open' to 'rejected'

p5pRT · 2016-05-03T02:02:49Z

From @jimav

Ok, thanks for the reference.

On 05/02/2016 03:03 PM, Father Chrysostomos via RT wrote:

On Mon May 02 14:41:04 2016, jim.avera@gmail.com wrote:

The sort operator has ‘extra special’ parsing rules.

sub mygrep (&@) { }

my @b = sort grep {1} keys %ENV; # works
my @a = mygrep {1} keys %ENV; # works
my @c = sort mygrep {1}, keys %ENV; # works
It compiles, but gives:

Sort subroutine didn't return single value at -e line 1.

because mygrep is the sort comparison routine, and {1}, keys %ENV (i.e., an anonymous hash, followed by the env var names) is the list of items to sort.

my @d = sort mygrep {1} keys %ENV; # syntax error "} keys"
Here, the list of items to sort is ({1} keys %ENV), which contains a syntax error.

Use +mygrep if you intend mygrep to be part of the source list. This is documented in perfunc:
        Warning&#8203;: syntactical care is required when sorting the list
        returned from a function\.  If you want to sort the list returned by
        the function call "find\_records$@&#8203;key$"\, you can use&#8203;:

            my @&#8203;contact = sort \{ $a cmp $b \} find\_records @&#8203;key;
            my @&#8203;contact = sort \+find\_records$@&#8203;key$;
            my @&#8203;contact = sort &find\_records$@&#8203;key$;
            my @&#8203;contact = sort$find\_records\(@&#8203;key$\);

        If instead you want to sort the array @&#8203;key with the comparison
        routine "find\_records" then you can use&#8203;:

            my @&#8203;contact = sort \{ find\_records \} @&#8203;key;
            my @&#8203;contact = sort find\_records$@&#8203;key$;
            my @&#8203;contact = sort$find\_records @&#8203;key$;
            my @&#8203;contact = sort$find\_records \(@&#8203;key$\);
Not a bug.

p5pRT closed this as completed May 2, 2016

p5pRT added the Severity Low label Oct 19, 2019

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sort mygrep {1} keys %hash ...will not compile #15304

sort mygrep {1} keys %hash ...will not compile #15304

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p5pRT commented May 3, 2016

sort mygrep {1} keys %hash ...will not compile #15304

sort mygrep {1} keys %hash ...will not compile #15304

Comments

p5pRT commented May 2, 2016

p5pRT commented May 2, 2016

From @jimav

p5pRT commented May 2, 2016

From @cpansprout

p5pRT commented May 2, 2016

p5pRT commented May 2, 2016

p5pRT commented May 3, 2016

From @jimav