Replace whitespace characters with escape codes in Tcl

space2escape.tcl

# Replace whitespace characters with their escape codes
#
# @param str String containing some whitespace
# @return New string with escapes instead of whitespace
proc space2escape str {
    set escapes {
        \b \\b
        \f \\f
        \n \\n
        \r \\r
        \t \\t
    }

    return [string map $escapes $str]
}