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author | Jim Meyering <jim@meyering.net> | 1999-10-02 11:46:53 +0000 |
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committer | Jim Meyering <jim@meyering.net> | 1999-10-02 11:46:53 +0000 |
commit | 46f2e4efeb2da93a2607fe020ed238b49c34cb96 (patch) | |
tree | e0616a9f05c871781d979a0c7fc4f45d79c65205 /doc/textutils.texi | |
parent | 6c4caf0dbfc4421270627f48bfcee585cc59cc12 (diff) | |
download | coreutils-46f2e4efeb2da93a2607fe020ed238b49c34cb96.tar.xz |
another example for tr -- illustrating problems with `-' in ranges..
Diffstat (limited to 'doc/textutils.texi')
-rw-r--r-- | doc/textutils.texi | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/doc/textutils.texi b/doc/textutils.texi index 16dd7d5a4..b424302ec 100644 --- a/doc/textutils.texi +++ b/doc/textutils.texi @@ -3640,14 +3640,14 @@ to remove all @samp{a}s, @samp{x}s, and @samp{M}s you would do this: tr -d axM @end example -However, when @samp{-} is one of those characters, it can be tricky -because @samp{-} has special meanings. -Performing the same task as above example but also +However, when @samp{-} is one of those characters, it can be tricky because +@samp{-} has special meanings. Performing the same task as above but also removing all @samp{-} characters, we might try @code{tr -d -axM}, but that would fail because @code{tr} would try to interpret @samp{-a} as a command-line option. Alternatively, we could try putting the hyphen inside the string, @code{tr -d a-xM}, but that wouldn't work either because -it'd make @code{tr} remove all characters in the range @samp{a}@dots{}@samp{x}. +it would make @code{tr} interpret @code{a-x} as the range of characters +@samp{a}@dots{}@samp{x} rather than the three. One way to solve the problem is to put the hyphen at the end of the list of characters: @@ -3656,7 +3656,7 @@ tr -d axM- @end example More generally, use the character class notation @code{[=c=]} -where you'd put @samp{-} (or any other character) in place of the @samp{c}: +with @samp{-} (or any other character) in place of the @samp{c}: @example tr -d '[=-=]axM' |