support for Real.isInfitite and isNan

docs/Real.md

@@ -19,6 +19,8 @@ you can use it's class to ensure type:
 |-----------------|-------------------------------------------------------------|------|
 | `.roundToInt()` | round to nearest int like round(x)                          | Int  |
 | `.toInt()`      | convert integer part of real to `Int` dropping decimal part | Int  |
+| `.isInfinite()` | true when the value is `Infinity` or `-Infinity`            | Bool |
+| `.isNaN()`      | true when the value is `NaN`                                | Bool |
 | `.clamp(range)` | clamp value within range boundaries                         | Real |
 |                 |                                                             |      |
 |                 |                                                             |      |