Re: ED on austingroupbugs

[Andrew L. Moore]

An updated commit with tests:
https://github.com/slewsys/ed/commit/42fd42b4e5764526d6089f03aa3e7ca88370142c

On 4/23/23 10:01, Andrew L. Moore wrote:

| For a given pattern delimiter, d, POSIX specifies that the delimiter
| can be included in the pattern if it is backslash-escaped (i.e., \d).
| So in the case d == '\\', the ed command `s\\\' should be equivalent
| to `s/\\//p'. My current implementation treated this as `s///'
| instead.
|
| The following commit fixes this (tests needed):
| 
https://github.com/slewsys/ed/commit/cd2c4db24927df7b0009f5a9f1d4338d72cdfd11
|
| GNU ed has an underlying bug: the command `s/pattern` is incorrectly
| flagged as an error due to a missing delimiter, whereas it has always
| been equivalent to `s/pattern//p'. Though not spelled out explicitly
| by POSIX, it is traditional behavior - and consistent with the line
| addressing expression `/pattern' (without terminating delimiter) which
| GNU ed does correctly handle.
|
| -AM
|
| On 4/23/23 10:01, Andrew L. Moore wrote:
|
| | On 4/22/23 02:59, vico@tuta.io wrote:
| |
| | | Maybe you haven't read it and you'll be interested:
| | | https://austingroupbugs.net/view.php?id=1662
| |
| |
| | POSIX does not allow a backslash delimiter in ex, but does not
| | disallow it for ed. And indeed, The Open Group testsuite for ed
| | does not complain if a backslash delimiter is supported.
| |
| |
| | I'm sharing this with GNU ed maintainer, Antonio Diaz, since a
| | single backslash (\) is permitted as a (admittedly weird) pattern
| | delimiter in GNU, macOS and *BSD ed as well, since they all share
| | the same codebase.
| |
| |
| | Thank you for the heads up!
| | -AM