started writing lexer after making string lib

string/docs/modify/upper.md

@@ -0,0 +1,23 @@
+# string_Upper
+Make a string uppercase.
+
+## Arguments
+- str (string): the string to make uppercase.
+
+## Returns
+upperString (string): the string in uppercase.
+
+## Raises
+- `AllocFail`: raised if Ground failed to allocate memory for the new string.
+
+## Example
+### Ground
+```python
+call !string_Upper "MY string" &upperString
+println $upperString # "MY STRING"
+```
+
+### Solstice
+```c
+puts string_Upper("MY string") // "MY STRING"
+```