sed: matching unicode blocks with

问题:

I am desperately trying to replace certain unicode characters (graphemes) from a file using sed. However I keep failing for some of them, namely the ones from unicode blocks:

\p{InHigh_Surrogates}: U+D800–U+DB7F
\p{InHigh_Private_Use_Surrogates}: U+DB80–U+DBFF
\p{InLow_Surrogates}: U+DC00–U+DFFF

I tried (in a sed config file loaded via the -f switch):

s/\p{InHigh_Surrogates}/###/  --> no effect at all
s/\\p\{InHigh_Surrogates\}/###_D-NON-UTF8_###/ -> error message 'Invalid content of \{\}'

Anybody got a suggestion? Also, I am not necessarily focused on using the blocks - but I also failed trying to define a character range of the form \xd800-\xdfff.

Thanks, Thomas

回答1:

Try using the -r flag for sed:

$ sed -r 's/\\p\{InHigh_Surrogates\}/###/g' file
###: U+D800–U+DB7F
\p{InHigh_Private_Use_Surrogates}: U+DB80–U+DBFF
\p{InLow_Surrogates}: U+DC00–U+DFFF

From man sed:

-r, --regexp-extended

use extended regular expressions in the script.