define external float function FP_v value stream numeric string

Used to initialize floating point values by converting a character string representing a floating point number into a float value. If the string does not represent a floating point number, the float value for NaN (not a number) is returned. FP_v converts the case-insensitive representations of the following strings into their floating point value counterparts:

• Infinity
• Inf
• +Inf
• -Infinity
• -Inf
• NaN

The following code demonstrates how to use FP_v to initialize the stream my-float using any digit that matches the specified pattern:

  ...
  find white-space (digit+("."digit*)?)=>found-float
  local float my-float
  set my-float to FP_v found-float