started writing lexer after making string lib

string/docs/classify/is_space.md

@@ -0,0 +1,24 @@
+# string_IsSpace
+Returns true if the given `string` is whitespace.
+
+## Arguments
+- str (string): the string to check.
+
+## Returns
+isAlpha (bool): returns `true` if `string` is whitespace, otherwise `false`.
+
+## Example
+### Ground
+```python
+call !string_IsAlpha "    " &isAlpha
+println $isAlpha # true
+
+call !string_IsAlpha " " &isAlpha
+println $isAlpha # true
+
+call !string_IsAlpha "abc_def" &isAlpha
+println $isAlpha # false
+
+call !string_IsAlpha "   a" &isAlpha
+println $isAlpha # false
+```