| Newsgroups |
gmane.editors.sed.user |
| Message-ID |
<[email protected]> |
--3NK1hnpwpH2i781DFxAyv5Rjku9TD0bGOuG3i3y
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Hi;
The question mark regular expression isn't doing what the info page https://www.gnu.org/software/sed/manual/sed.html#index-GNU-extensions_002c-to-basic-regular-expressions-2 says:
> echo 'one?two' | sed 's/e\?//'
one?two
But if backslash-? is by itself, it's treated as a literal character:
> echo 'one?two' | sed 's/\?//'
onetwo
Same for ? by itself:
> echo 'one?two' | sed 's/?//'
onetwo
Double-backslash-? doesn't do anything:
> echo 'one?two' | sed 's/e\\?//'
one?two
It finally works right with three backslashes:
> echo 'one?two' | sed 's/e\\\?//'
on?two
=====
Here it is with the extended regexp flag (-r):
> echo 'one?two' | sed -r 's/e?//'
one?two # Did nothing
> echo 'one?two' | sed -r 's/e\?//'
ontwo # Matched both 'e' and '?'
> echo 'one?two' | sed -r 's/e\\?//'
on?two # Matched one 'e'
> echo 'one?two' | sed -r 's/e\\\?//'
one?two # Didn't match
=====
The plus sign (shown in the info page just above the question mark) works as the man page says it should:
> echo 'one+two' | sed 's/e+//'
ontwo
> echo 'one+two' | sed 's/e\+//'
on+two
> echo 'one+two' | sed -r 's/e+//'
on+two
> echo 'one+two' | sed -r 's/e\+//'
ontwo
======
This is in sed-4.7 http://ftp.gnu.org/gnu/sed/sed-4.7.tar.xz , the current version as of today (2019-09-14), but it's doing this in version 4.2.2 as well.
At this point, would it be better to fix the behaviour of sed or edit the man page?
Thanks!
[Non-text portions of this message have been removed]
--3NK1hnpwpH2i781DFxAyv5Rjku9TD0bGOuG3i3y
Content-Type: text/html; charset=UTF-8
Content-Transfer-Encoding: 7bit
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
</head>
<body style="background-color: #fff;">
<span style="display:none"> </span>
<!--~-|**|PrettyHtmlStartT|**|-~-->
<div id="ygrp-mlmsg" style="position:relative;">
<div id="ygrp-msg" style="z-index: 1;">
<!--~-|**|PrettyHtmlEndT|**|-~-->
<div id="ygrp-text" >
<p>Hi;<br>
<br>
<br>
The question mark regular expression isn't doing what the info page https://www.gnu.org/software/sed/manual/sed.html#index-GNU-extensions_002c-to-basic-regular-expressions-2 says:<br>
> echo 'one?two' | sed 's/e\?//'<br>
one?two<br>
<br>
<br>
But if backslash-? is by itself, it's treated as a literal character:<br>
> echo 'one?two' | sed 's/\?//'<br>
onetwo<br>
<br>
<br>
Same for ? by itself:<br>
> echo 'one?two' | sed 's/?//'<br>
onetwo<br>
<br>
<br>
Double-backslash-? doesn't do anything:<br>
> echo 'one?two' | sed 's/e\\?//'<br>
<br>
one?two<br>
<br>
<br>
It finally works right with three backslashes:<br>
> echo 'one?two' | sed 's/e\\\?//'<br>
<br>
on?two<br>
=====<br>
<br>
<br>
Here it is with the extended regexp flag (-r):<br>
<br>
<br>
> echo 'one?two' | sed -r 's/e?//'<br>
one?two # Did nothing<br>
> echo 'one?two' | sed -r 's/e\?//'<br>
ontwo # Matched both 'e' and '?'<br>
> echo 'one?two' | sed -r 's/e\\?//'<br>
on?two # Matched one 'e'<br>
> echo 'one?two' | sed -r 's/e\\\?//'<br>
one?two # Didn't match<br>
<br>
<br>
=====<br>
<br>
<br>
The plus sign (shown in the info page just above the question mark) works as the man page says it should:<br>
> echo 'one+two' | sed 's/e+//'<br>
ontwo<br>
> echo 'one+two' | sed 's/e\+//'<br>
on+two<br>
<br>
<br>
> echo 'one+two' | sed -r 's/e+//'<br>
<br>
on+two<br>
> echo 'one+two' | sed -r 's/e\+//'<br>
ontwo<br>
<br>
<br>
======<br>
<br>
This is in sed-4.7 http://ftp.gnu.org/gnu/sed/sed-4.7.tar.xz , the current version as of today (2019-09-14), but it's doing this in version 4.2.2 as well.<br>
<br>
<br>
At this point, would it be better to fix the behaviour of sed or edit the man page?<br>
<br>
<br>
Thanks!<br>
<br>
[Non-text portions of this message have been removed]<br>
<br>
</p>
</div>
<!--~-|**|PrettyHtmlStart|**|-~-->
<div style="color: #fff; height: 0;">__._,_.___</div>
<div style="clear:both"> </div>
<div id="fromDMARC" style="margin-top: 10px;">
<hr style="height:2px ; border-width:0; color:#E3E3E3; background-color:#E3E3E3;">
Posted by: [email protected] <hr style="height:2px ; border-width:0; color:#E3E3E3; background-color:#E3E3E3;">
</div>
<div style="clear:both"> </div>
<table cellspacing=4px style="margin-top: 10px; margin-bottom: 10px; color: #2D50FD;">
<tbody>
<tr>
<td style="font-size: 12px; font-family: arial; font-weight: bold; padding: 7px 5px 5px;" >
<a style="text-decoration: none; color: #2D50FD" href="https://groups.yahoo.com/neo/groups/sed-users/conversations/messages/9993;_ylc=X3oDMTJwYjdzajE3BF9TAzk3MzU5NzE0BGdycElkAzI0ODk2MzkEZ3Jwc3BJZAMxNzA5MzM1MDAyBG1zZ0lkAzk5OTMEc2VjA2Z0cgRzbGsDcnBseQRzdGltZQMxNTY4NTc5NDMy?act=reply&messageNum=9993">Reply via web post</a>
</td>
<td>•</td>
<td style="font-size: 12px; font-family: arial; padding: 7px 5px 5px;" >
<a href="mailto:[email protected]?subject=Re%3A%20Bug%20report%20for%20sed%204%2E2%2E2%3A%20%27%3F%27%20not%20working%20in%20basic%20regexps%3F" style="text-decoration: none; color: #2D50FD;">
Reply to sender </a>
</td>
<td>•</td>
<td style="font-size: 12px; font-family: arial; padding: 7px 5px 5px;">
<a href="mailto:[email protected]?subject=Re%3A%20Bug%20report%20for%20sed%204%2E2%2E2%3A%20%27%3F%27%20not%20working%20in%20basic%20regexps%3F" style="text-decoration: none; color: #2D50FD">
Reply to group </a>
</td>
<td>•</td>
<td style="font-size: 12px; font-family: arial; padding: 7px 5px 5px;" >
<a href="https://groups.yahoo.com/neo/groups/sed-users/conversations/newtopic;_ylc=X3oDMTJldDZndmRvBF9TAzk3MzU5NzE0BGdycElkAzI0ODk2MzkEZ3Jwc3BJZAMxNzA5MzM1MDAyBHNlYwNmdHIEc2xrA250cGMEc3RpbWUDMTU2ODU3OTQzMg--" style="text-decoration: none; color: #2D50FD">Start a New Topic</a>
</td>
<td>•</td>
<td style="font-size: 12px; font-family: arial; padding: 7px 5px 5px;color: #2D50FD;" >
<a href="https://groups.yahoo.com/neo/groups/sed-users/conversations/topics/9993;_ylc=X3oDMTM0OTJub3FoBF9TAzk3MzU5NzE0BGdycElkAzI0ODk2MzkEZ3Jwc3BJZAMxNzA5MzM1MDAyBG1zZ0lkAzk5OTMEc2VjA2Z0cgRzbGsDdnRwYwRzdGltZQMxNTY4NTc5NDMyBHRwY0lkAzk5OTM-" style="text-decoration: none; color: #2D50FD;">Messages in this topic</a>
(1)
</td>
</tr>
</tbody>
</table>
<!------- Start Nav Bar ------>
<div id="ygrp-grfd" style="font-family: Verdana; font-size: 12px; padding: 15px 0;">
<!-- |**|begin egp html banner|**| -->
-- <BR>
<!-- |**|end egp html banner|**| -->
</div>
<!-- |**|begin egp html banner|**| -->
<div id="ygrp-vital" style="background-color: #f2f2f2; font-family: Verdana; font-size: 10px; margin-bottom: 10px; padding: 10px;">
<span id="vithd" style="font-weight: bold; color: #333; text-transform: uppercase; "><a href="https://groups.yahoo.com/neo/groups/sed-users/info;_ylc=X3oDMTJlOHNob2MzBF9TAzk3MzU5NzE0BGdycElkAzI0ODk2MzkEZ3Jwc3BJZAMxNzA5MzM1MDAyBHNlYwN2dGwEc2xrA3ZnaHAEc3RpbWUDMTU2ODU3OTQzMg--" style="text-decoration: none;">Visit Your Group</a></span>
<ul style="list-style-type: none; margin: 0; padding: 0; display: inline;">
</ul>
</div>
<div id="ft" style="font-family: Arial; font-size: 11px; margin-top: 5px; padding: 0 2px 0 0; clear: both;">
<a href="https://groups.yahoo.com/neo;_ylc=X3oDMTJkNThnb2gxBF9TAzk3MzU5NzE0BGdycElkAzI0ODk2MzkEZ3Jwc3BJZAMxNzA5MzM1MDAyBHNlYwNmdHIEc2xrA2dmcARzdGltZQMxNTY4NTc5NDMy" style="float: left;"><img src="http://l.yimg.com/ru/static/images/yg/img/email/new_logo/logo-groups-137x15.png" height="15" width="137" alt="Yahoo! Groups" style="border: 0;"/></a>
<div style="color: #747575; float: right;"> • <a href="https://info.yahoo.com/privacy/us/yahoo/groups/details.html" style="text-decoration: none;">Privacy</a> • <a href="mailto:[email protected]?subject=Unsubscribe" style="text-decoration: none;">Unsubscribe</a> • <a href="https://info.yahoo.com/legal/us/yahoo/utos/terms/" style="text-decoration: none;">Terms of Use</a> </div>
</div>
<br>
<!-- |**|end egp html banner|**| -->
</div> <!-- ygrp-msg -->
<!-- Sponsor -->
<!-- |**|begin egp html banner|**| -->
<div id="ygrp-sponsor" style="width:160px; float:right; clear:none; margin:0 0 25px 0; background: #fff;">
<!-- Start Recommendations -->
<div id="ygrp-reco">
</div>
<!-- End Recommendations -->
</div> <!-- |**|end egp html banner|**| -->
<div style="clear:both; color: #FFF; font-size:1px;">.</div>
</div>
<img src="http://geo.yahoo.com/serv?s=97359714/grpId=2489639/grpspId=1709335002/msgId=9993/stime=1568579432" width="1" height="1"> <br>
<img src="http://y.analytics.yahoo.com/fpc.pl?ywarid=515FB27823A7407E&a=10001310322279&js=no&resp=img" width="1" height="1">
<div style="color: #fff; height: 0;">__,_._,___</div>
<!--~-|**|PrettyHtmlEnd|**|-~-->
</body>
<!--~-|**|PrettyHtmlStart|**|-~-->
<head>
<style type="text/css">
<!--
#ygrp-mkp {
border: 1px solid #d8d8d8;
font-family: Arial;
margin: 10px 0;
padding: 0 10px;
}
#ygrp-mkp hr {
border: 1px solid #d8d8d8;
}
#ygrp-mkp #hd {
color: #628c2a;
font-size: 85%;
font-weight: 700;
line-height: 122%;
margin: 10px 0;
}
#ygrp-mkp #ads {
margin-bottom: 10px;
}
#ygrp-mkp .ad {
padding: 0 0;
}
#ygrp-mkp .ad p {
margin: 0;
}
#ygrp-mkp .ad a {
color: #0000ff;
text-decoration: none;
}
#ygrp-sponsor #ygrp-lc {
font-family: Arial;
}
#ygrp-sponsor #ygrp-lc #hd {
margin: 10px 0px;
font-weight: 700;
font-size: 78%;
line-height: 122%;
}
#ygrp-sponsor #ygrp-lc .ad {
margin-bottom: 10px;
padding: 0 0;
}
#actions {
font-family: Verdana;
font-size: 11px;
padding: 10px 0;
}
#activity {
background-color: #e0ecee;
float: left;
font-family: Verdana;
font-size: 10px;
padding: 10px;
}
#activity span {
font-weight: 700;
}
#activity span:first-child {
text-transform: uppercase;
}
#activity span a {
color: #5085b6;
text-decoration: none;
}
#activity span span {
color: #ff7900;
}
#activity span .underline {
text-decoration: underline;
}
.attach {
clear: both;
display: table;
font-family: Arial;
font-size: 12px;
padding: 10px 0;
width: 400px;
}
.attach div a {
text-decoration: none;
}
.attach img {
border: none;
padding-right: 5px;
}
.attach label {
display: block;
margin-bottom: 5px;
}
.attach label a {
text-decoration: none;
}
blockquote {
margin: 0 0 0 4px;
}
.bold {
font-family: Arial;
font-size: 13px;
font-weight: 700;
}
.bold a {
text-decoration: none;
}
dd.last p a {
font-family: Verdana;
font-weight: 700;
}
dd.last p span {
margin-right: 10px;
font-family: Verdana;
font-weight: 700;
}
dd.last p span.yshortcuts {
margin-right: 0;
}
div.attach-table div div a {
text-decoration: none;
}
div.attach-table {
width: 400px;
}
div.file-title a, div.file-title a:active, div.file-title a:hover, div.file-title a:visited {
text-decoration: none;
}
div.photo-title a, div.photo-title a:active, div.photo-title a:hover, div.photo-title a:visited {
text-decoration: none;
}
div#ygrp-mlmsg #ygrp-msg p a span.yshortcuts {
font-family: Verdana;
font-size: 10px;
font-weight: normal;
}
.green {
color: #628c2a;
}
.MsoNormal {
margin: 0 0 0 0;
}
o {
font-size: 0;
}
#photos div {
float: left;
width: 72px;
}
#photos div div {
border: 1px solid #666666;
height: 62px;
overflow: hidden;
width: 62px;
}
#photos div label {
color: #666666;
font-size: 10px;
overflow: hidden;
text-align: center;
white-space: nowrap;
width: 64px;
}
#reco-category {
font-size: 77%;
}
#reco-desc {
font-size: 77%;
}
.replbq {
margin: 4px;
}
#ygrp-actbar div a:first-child {
/* border-right: 0px solid #000;*/
margin-right: 2px;
padding-right: 5px;
}
#ygrp-mlmsg {
font-size: 13px;
font-family: Arial, helvetica,clean, sans-serif;
*font-size: small;
*font: x-small;
}
#ygrp-mlmsg table {
font-size: inherit;
font: 100%;
}
#ygrp-mlmsg select, input, textarea {
font: 99% Arial, Helvetica, clean, sans-serif;
}
#ygrp-mlmsg pre, code {
font:115% monospace;
*font-size:100%;
}
#ygrp-mlmsg * {
line-height: 1.22em;
}
#ygrp-mlmsg #logo {
padding-bottom: 10px;
}
#ygrp-msg p a {
font-family: Verdana;
}
#ygrp-msg p#attach-count span {
color: #1E66AE;
font-weight: 700;
}
#ygrp-reco #reco-head {
color: #ff7900;
font-weight: 700;
}
#ygrp-reco {
margin-bottom: 20px;
padding: 0px;
}
#ygrp-sponsor #ov li a {
font-size: 130%;
text-decoration: none;
}
#ygrp-sponsor #ov li {
font-size: 77%;
list-style-type: square;
padding: 6px 0;
}
#ygrp-sponsor #ov ul {
margin: 0;
padding: 0 0 0 8px;
}
#ygrp-text {
font-family: Georgia;
}
#ygrp-text p {
margin: 0 0 1em 0;
}
#ygrp-text tt {
font-size: 120%;
}
#ygrp-vital ul li:last-child {
border-right: none !important;
}
-->
</style>
</head>
<!--~-|**|PrettyHtmlEnd|**|-~-->
</html>
<!-- end group email -->
--3NK1hnpwpH2i781DFxAyv5Rjku9TD0bGOuG3i3y--