For example, "/{asterisk}.c" matches "cat-file.c" but not
"mozilla-sha1/sha1.c".
+Two consecutive asterisks ("`**`") in patterns matched against
+full pathname may have special meaning:
+
+ - A leading "`**`" followed by a slash means match in all
+ directories. For example, "`**/foo`" matches file or directory
+ "`foo`" anywhere, the same as pattern "`foo`". "**/foo/bar"
+ matches file or directory "`bar`" anywhere that is directly
+ under directory "`foo`".
+
+ - A trailing "/**" matches everything inside. For example,
+ "abc/**" matches all files inside directory "abc", relative
+ to the location of the `.gitignore` file, with infinite depth.
+
+ - A slash followed by two consecutive asterisks then a slash
+ matches zero or more directories. For example, "`a/**/b`"
+ matches "`a/b`", "`a/x/b`", "`a/x/y/b`" and so on.
+
+ - Other consecutive asterisks are considered invalid.
+
NOTES
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