apparent parsing error with not(arg)

[p5pRT]

Migrated from rt.perl.org#1550 (status was 'resolved')

Searchable as RT1550$

[p5pRT]

From sburke@netadventure.net

This
  print grep(not($_), 0,'', 0.0, 1,11),
generates a syntax error​:
  Not enough arguments for grep at - line 1, near "11)"

Of course, I simply do this instead​:
  print grep(!($_), 0,'', 0.0, 1,11),
which works fine, as does
  print grep { not($_) } 0,'', 0.0, 1,11,

Perlop says not() is the equivalent of "!" except for the very low
precedence. Since it's unary, and I'm providing parens, predecence
seems irrelevent here. I once mentioned this to Tom a long time ago,
and he mentioned something involving the difference between parsing
functions (as I wished to pretend not(ARG) is) and parsing operators
(which not() really is), but it all rather went over my head.

Here's my version info​:
ttyp5 sburke ~ stonehenge 21​: perl -V
Summary of my perl5 (5.0 patchlevel 4 subversion 4) configuration​:
  Platform​:
  osname=bsdos, osvers=3.0, archname=i386-bsdos
  uname='bsdos stonehenge.netadventure.com 3.0 bsdi bsdos 3.0 kernel #0​: mon jul 28 00​:40​:29 pdt 1997 ken@​stonehenge.netadventure.com​:usrsrcsyscompilelocal i386 '
  hint=recommended, useposix=true, d_sigaction=define
  bincompat3=y useperlio=undef d_sfio=undef
  Compiler​:
  cc='shlicc2', optimize='-O2', gccversion=2.7.2.1
  cppflags='-I/usr/local/include'
  ccflags ='-I/usr/local/include'
  stdchar='char', d_stdstdio=undef, usevfork=false
  voidflags=15, castflags=0, d_casti32=define, d_castneg=define
  intsize=4, alignbytes=4, usemymalloc=n, prototype=define
  Linker and Libraries​:
  ld='shlicc2', ldflags =' -L/usr/X11/lib -L/usr/local/lib'
  libpth=/usr/local/lib /usr/shlib /shlib /usr/lib /usr/X11/lib
  libs=-lrpc -lcurses -ltermcap -lXpm -lXaw -lXmu -lXt -lSM -lICE -lXext -lX11 -ldl -lm -lc
  libc=/usr/lib/libc.a, so=o
  useshrplib=false, libperl=libperl.a
  Dynamic Linking​:
  dlsrc=dl_dlopen.xs, dlext=o, d_dlsymun=undef, ccdlflags=' '
  cccdlflags=' ', lddlflags='-r -L/usr/X11/lib -L/usr/local/lib'

Characteristics of this binary (from libperl)​:
  Built under bsdos
  Compiled at Dec 31 1997 19​:45​:20
  @​INC​:
  /usr/local/lib/perl5/i386-bsdos/5.00404
  /usr/local/lib/perl5
  /usr/local/lib/perl5/site_perl/i386-bsdos
  /usr/local/lib/perl5/site_perl
  .

I get identical results on a box with this config info​:

lachler ~ musca​:pts/24 3​: perl -V
Summary of my perl5 (5.0 patchlevel 5 subversion 3) configuration​:
  Platform​:
  osname=aix, osvers=4.3.1.0, archname=aix
  uname='aix pegasus 3 4 000165185700 '
  hint=recommended, useposix=true, d_sigaction=define
  usethreads=undef useperlio=undef d_sfio=undef
  Compiler​:
  cc='cc', optimize='-O', gccversion=
  cppflags='-D_ALL_SOURCE -D_ANSI_C_SOURCE -D_POSIX_SOURCE -qmaxmem=8192 -I/usr/local/include -I/usr/local/gnu/include'
  ccflags ='-D_ALL_SOURCE -D_ANSI_C_SOURCE -D_POSIX_SOURCE -qmaxmem=8192 -I/usr/local/include -I/usr/local/gnu/include'
  stdchar='unsigned char', d_stdstdio=define, usevfork=false
  intsize=4, longsize=4, ptrsize=4, doublesize=8
  d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=8
  alignbytes=8, usemymalloc=n, prototype=define
  Linker and Libraries​:
  ld='ld', ldflags ='-L/usr/local/lib -L/usr/local/gnu/lib -L/usr/ccs/lib -L/lib'
  libpth=/usr/local/lib /lib /usr/lib /usr/ccs/lib /usr/local/gnu/lib
  libs=-lnsl -lgdbm -ldbm -ldl -lld -lm -lc -lcrypt -lbsd -lPW
  libc=, so=a, useshrplib=false, libperl=libperl.a
  Dynamic Linking​:
  dlsrc=dl_aix.xs, dlext=so, d_dlsymun=undef, ccdlflags='-bE​:perl.exp'
  cccdlflags=' ', lddlflags='-bhalt​:4 -bM​:SRE -bI​:$(PERL_INC)/perl.exp -bE​:$(BASEEXT).exp -b noentry -lc -L/usr/local/lib -L/usr/local/gnu/lib -L/usr/ccs/lib -L/lib'

Characteristics of this binary (from libperl)​:
  Built under aix
  Compiled at Aug 12 1999 09​:10​:29
  %ENV​:
  PERLLIB="/nfs/user/l/lachler/.bin/perl"
  @​INC​:
  /nfs/user/l/lachler/.bin/perl
  /usr/local/gnu/lib/perl5/5.00503/aix
  /usr/local/gnu/lib/perl5/5.00503
  /usr/local/gnu/lib/perl5/site_perl/5.005/aix
  /usr/local/gnu/lib/perl5/site_perl/5.005
  .

And even on MacPerl 5.2.0r4 (patchlevel 5.004) with the following -V​:
Summary of my ( patchlevel 0 subversion ) configuration​:
  Platform​:
  osname=MacOS, osvers=7.5, archname=
  uname=''
  hint=, useposix=true, d_sigaction=
  bincompat3= useperlio= d_sfio=
  Compiler​:
  cc='C', optimize='', gccversion=
  cppflags=''
  ccflags =''
  stdchar='', d_stdstdio=define, usevfork=
  voidflags=, castflags=0, d_casti32=32, d_castneg=define
  intsize=32, alignbytes=, usemymalloc=, randbits=
  Linker and Libraries​:
  ld='', ldflags =''
  libpth=
  libs=
  libc=, so=
  useshrplib=, libperl=
  Dynamic Linking​:
  dlsrc=, dlext=, d_dlsymun=, ccdlflags=''
  cccdlflags='', lddlflags=''

Characteristics of this binary (from libperl)​:
  Compile-time options​: MULTIPLICITY
  Built under MacOS
  Compiled at Apr 3 1998 21​:45​:13
  %ENV​:
  PERL5LIB="Slig​:MacPerl :site_perl,Slig​:MacPerl :lib,WebSites​:Sean,WebSites​:,Slig​:WIP Slig​:cgi-bin,Slig​:MacPerl :site_perl_dyna"
  @​INC​:
  Slig​:MacPerl :site_perl​:
  Slig​:MacPerl :lib​:MacPPC​:
  Slig​:MacPerl :lib​:
  WebSites​:Sean​:MacPPC​:
  WebSites​:Sean​:
  WebSites​:
  Slig​:WIP Slig​:cgi-bin​:
  Slig​:MacPerl :site_perl_dyna​:
  Slig​:MacPerl :lib​:MacPPC​:
  Slig​:MacPerl :lib​:
  Slig​:MacPerl :site_perl​:
  :
  Dev​:Pseudo​:

--
Sean M. Burke sburke@​netadventure.net http​://www.netadventure.net/~sburke/

[p5pRT]

From @TimToady

Sean M. Burke writes​:
: Not exactly an earth-shaking bug, but don't say I never told ya​:
:
: This
: print grep(not($_), 0,'', 0.0, 1,11),
: generates a syntax error​:
: Not enough arguments for grep at - line 1, near "11)"

Hmm. I wonder how many programs we'll break by fixing this.

Nevertheless, here's something resembling a patch, if we decide to
fix it.

Inline Patch

--- /kiev/src/perl5.005_61our/toke.c	Fri Sep 24 16:06:45 1999
+++ toke.c	Wed Oct  6 10:39:00 1999
@@ -120,7 +120,7 @@
  * LOOPX        : loop exiting command (goto, last, dump, etc)
  * FTST         : file test operator
  * FUN0         : zero-argument function
- * FUN1         : not used
+ * FUN1         : not used, except for not, which isn't a UNIOP
  * BOop         : bitwise or or xor
  * BAop         : bitwise and
  * SHop         : shift operator
@@ -4096,7 +4104,10 @@
 	    OPERATOR(USE);
 
 	case KEY_not:
-	    OPERATOR(NOTOP);
+	    if (*s == '(' || (s = skipspace(s), *s == '('))
+		FUN1(NOTOP);
+	    else
+		OPERATOR(NOTOP);
 
 	case KEY_open:
 	    s = skipspace(s);

Larry