Read a number in any of the formats that Perl accepts:
- 0(x[0-7A-F]+)|([0-7]+)|(b[01])
- \d([\d_]*\d)?(\.\d([\d_]*\d)?)?[Ee](\d+)
-
- Underbars (_) are allowed in decimal numbers. If -w is on,
- underbars must not be consecutive, and they cannot start
- or end integer or fractional parts.
+ \d(_?\d)*(\.(\d(_?\d)*)?)?[Ee](\d+) 12 12.34 12.
+ \.\d(_?\d)*[Ee](\d+) .34
+ 0b[01](_?[01])*
+ 0[0-7](_?[0-7])*
+ 0x[0-9A-Fa-f](_?[0-9A-Fa-f])*
Like most scan_ routines, it uses the PL_tokenbuf buffer to hold the
thing it reads.