GNU bug report logs - #66411
sed --debug option prints the contents of the hold space after running the 'g' command

Previous Next

Full log

Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Zachary Santer <zsanter <at> gmail.com>
To: bug-sed <at> gnu.org
Subject: sed --debug option prints the contents of the hold space after
 running the 'g' command
Date: Sun, 8 Oct 2023 12:30:57 -0400

The 'g' command "[r]eplace[s] the contents of the pattern space with
the contents of the hold space." Outputting the contents of the hold
space then gives you the contents of the pattern space, but it still
doesn't make a lot of sense to do. It's not the hold space that was
updated. It's the pattern space.

$ seq 3 | sed --binary --regexp-extended --debug --expression='x; g; h'
SED PROGRAM:
  x
  g
  h
INPUT:   'STDIN' line 1
PATTERN: 1
COMMAND: x
PATTERN:
HOLD:    1
COMMAND: g
HOLD:    1
COMMAND: h
HOLD:    1
END-OF-CYCLE:
1
INPUT:   'STDIN' line 2
PATTERN: 2
COMMAND: x
PATTERN: 1
HOLD:    2
COMMAND: g
HOLD:    2
COMMAND: h
HOLD:    2
END-OF-CYCLE:
2
INPUT:   'STDIN' line 3
PATTERN: 3
COMMAND: x
PATTERN: 2
HOLD:    3
COMMAND: g
HOLD:    3
COMMAND: h
HOLD:    3
END-OF-CYCLE:
3

'x' updates both pattern and hold spaces, and you get the contents of
both in the debugging output. 'h' updates the hold space, and you get
the contents of the hold space in the debugging output. 'g' updates
the pattern space, and you get the contents of the hold space in the
debugging output.

$ sed --version
sed (GNU sed) 4.9
[...]
$ pacman --query sed
sed 4.9-1

Being run in MSYS2 MINGW64 terminal on Windows 10.

Thanks,
Zack

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.