Regular Expressions in JLex (2)

• [S] means any of a set of characters described by S.
  [ $\!\!$S] means any character not described by S.
  • [abc] is the same as EBNF ("a" | "b" | "c")
  • [a-cxyz] is the same as EBNF ("a" | "b" | "c" | "x" | "y" | "z")
  • [ $\!\!$xz] matches anything but x or z
• . matches everything but a newline. It is the same as [ $\!\!$$\backslash$n]

Examples:

• [0-9]+ describes integer numbers.
• $\backslash$"[ $\!\!$$\backslash$"]*$\backslash$" describes simple strings without escapes.

Q: Write JLex regular expressions for noStarOrSlash and floating point numbers!