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# missing arg
hg cat: invalid arguments
hg cat [OPTION]... FILE...
output the current or given revision of files
Print the specified files as they were at the given revision. If no
revision is given, the parent of the working directory is used, or tip if
no revision is checked out.
Output may be to a file, in which case the name of the file is given using
a format string. The formatting rules are the same as for the export
command, with the following additions:
"%s" basename of file being printed
"%d" dirname of file being printed, or '.' if in repository root
"%p" root-relative path name of file being printed
Returns 0 on success.
options:
-o --output FORMAT print output to file with formatted name
-r --rev REV print the given revision
--decode apply any matching decode filter
-I --include PATTERN [+] include names matching the given patterns
-X --exclude PATTERN [+] exclude names matching the given patterns
[+] marked option can be specified multiple times
use "hg -v help cat" to show global options
% [defaults]
a
a: no such file in rev 000000000000
% no repo
abort: There is no Mercurial repository here (.hg not found)!