I've added a pager to my command. So is there any option to search any string case-insensitive?
Then it really depends on your pager. See -i and -I options in man 1 less for less (also mind that less in turn depends on your system regex library - use ldd $(which less) to check - usually should be pcre standard perl regex). Otherwise you should search the docs of your pager.
I think what @rajeshisnepali wanted is more like less -i. For exmaple, cat somefile.txt | less -i.
bat can't do this trick.
-- update --
But you can bat somefile.txt and type -i to enable ignore case.

@archongum bat somefile.txt and typing -i didn't work for me.
Here's a quick screencast.
https://www.dropbox.com/s/8jqgwbbe9fow84y/bat_case_insensitive_not_working.webm?dl=0
Here's a quick screencast.
https://www.dropbox.com/s/8jqgwbbe9fow84y/bat_case_insensitive_not_working.webm?dl=0
@rajeshisnepali I think ignore case mode only effected when searching with pure lower case string. If the searching string contains A single uppercase character, ignore case mode won't work anymore.
These two pictures below are searching in ignore case mode.


You can also use the --pager option in the config file to always pass -i to less (see README for details).
Oh yes, for bat 0.15.4 and newer I believe the default pager is set as of less. I've aliased both cat & less to bat to perform accordingly.
I'm just trying this now (on Arch); with export PAGER="/usr/bin/less -RFI" then bat /some/file, it doesn't work, but if I do bat --pager "less -RFI" /some/file it does work. I'm quite confused by this.
PAGER will be overwritten by BAT_PAGER (have you set this?), which will be overwritten by --pager=… settings in the config file or the command line.
I don't have a bat config nor BAT_PAGER set, but setting BAT_PAGER resolved this, thanks :)
I don't have a
batconfig norBAT_PAGERset, but settingBAT_PAGERresolved this, thanks :)
Oh - right. If we detect less in PAGER, we actually overwrite the command line options (to make sure -R is included). So using BAT_PAGER or the config file is the only option here.
It would be great if someone could add this to the README.
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@rajeshisnepali I think ignore case mode only effected when searching with pure lower case string. If the searching string contains A single uppercase character, ignore case mode won't work anymore.


These two pictures below are searching in ignore case mode.