80 \item strings are enclosed by \texttt{"\ldots"} and consisting of |
80 \item strings are enclosed by \texttt{"\ldots"} and consisting of |
81 symbols, whitespaces and digits |
81 symbols, whitespaces and digits |
82 \item parentheses are \texttt{(}, \texttt{\{}, \texttt{)} and \texttt{\}} |
82 \item parentheses are \texttt{(}, \texttt{\{}, \texttt{)} and \texttt{\}} |
83 \item there are semicolons \texttt{;} |
83 \item there are semicolons \texttt{;} |
84 \item whitespaces are either \texttt{" "} (one or more) or \texttt{$\backslash$n} or |
84 \item whitespaces are either \texttt{" "} (one or more) or \texttt{$\backslash$n} or |
85 \texttt{$\backslash$t} |
85 \texttt{$\backslash$t} or \texttt{$\backslash$r} |
86 \item identifiers are letters followed by underscores \texttt{\_\!\_}, letters |
86 \item identifiers are letters followed by underscores \texttt{\_\!\_}, letters |
87 or digits |
87 or digits |
88 \item numbers are \pcode{0}, \pcode{1}, \ldots and so on; give |
88 \item numbers are \pcode{0}, \pcode{1}, \ldots and so on; give |
89 a regular expression that can recognise \pcode{0}, but not numbers |
89 a regular expression that can recognise \pcode{0}, but not numbers |
90 with leading zeroes, such as \pcode{001} |
90 with leading zeroes, such as \pcode{001} |