Lexical There is a tiny bit of processing before the lexer is executed. Two things happen before the lexical analysis starts, in order: First, the start of the file is checked for the UTF-8 BOM (\xEF\xBB\xBF). If the sequence is found, the relevant bytes are discarded. Note that it is strongly recommended to save Coyote files without the BOM. This matches (although more sternly) the Unicode consortium recommendation. However, it is supported for compatibility with some non-cooperating editors.