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+# csvre
+
+A simple tool for replacing data in CSV columns with regular
+expressions.
+
+## USAGE
+
+    csvre [options] --column=COLUMN <regex> <replacement>
+    csvre (-h | --help)
+    csvre --version
+
+## ARGUMENTS
+
+    <regex>
+
+        Regular expression used for matching.
+
+        For syntax documentation, see
+        https://docs.rs/regex/1.1.2/regex/#syntax
+
+        Some information about unicode handling can be found from
+        https://docs.rs/regex/1.1.2/regex/#unicode
+
+    <replacement>
+
+        Replacement string.
+
+        You can reference named capture groups in the regex with $name and
+        ${name} syntax. You can also use integers to reference capture
+        groups with $0 being the whole match, $1 the first group and so on.
+
+        If a capture group is not valid (name does not exist or index is
+        invalid), it is replaced with the empty string.
+
+        To insert a literal $, use $$.
+
+## OPTIONS
+
+    -h, --help
+
+        Show this message.
+
+    --version
+
+        Show the version number.
+
+    -d DELIM, --delimiter=DELIM
+
+        Field delimiter. This is used for both input and output.
+        [default: ,]
+
+    -c COLUMN, --column=COLUMN
+
+        Which column to operate on.
+
+        You can either use the column name or zero based index. If
+        you specify --no-headers, then you can only use the index
+        here.
+
+    -n, --no-headers
+
+        The input does not have a header row.
+
+        If you use this option, you can do matching against the first
+        row of input.
+
+    -b, --bytes
+
+        Don't assume utf-8 input, work on raw bytes instead.
+
+        See https://docs.rs/regex/1.1.2/regex/bytes/index.html#syntax
+        for differences to the normal matching rules.