Implement more string functions

src/built_in_functions/string.rs

@@ -282,7 +282,27 @@ impl StringFunction {
 
                 Value::none()
             }
-            StringFunction::Remove => todo!(),
+            StringFunction::Remove => {
+                Error::expect_argument_amount(self.name(), 2, arguments.len())?;
+
+                let mut string = arguments.get(0).unwrap().as_string_mut()?;
+                let index = arguments.get(1).unwrap().as_integer()? as usize;
+                let mut chars = string.chars().collect::<Vec<char>>();
+
+                if index <= chars.len() - 1 {
+                    let removed = chars.remove(index);
+                    let new_string = chars
+                        .iter()
+                        .map(|char| char.to_string())
+                        .collect::<String>();
+
+                    *string = new_string;
+
+                    Value::some(Value::string(removed))
+                } else {
+                    Value::none()
+                }
+            }
             StringFunction::ReplaceRange => todo!(),
             StringFunction::Retain => todo!(),
             StringFunction::Split => {

src/value/mod.rs

@@ -47,8 +47,8 @@ impl Default for Value {
 }
 
 impl Value {
-    pub fn string(string: String) -> Self {
-        Value::String(Arc::new(RwLock::new(string)))
+    pub fn string<T: Into<String>>(string: T) -> Self {
+        Value::String(Arc::new(RwLock::new(string.into())))
     }
 
     pub fn r#type(&self) -> Type {
@@ -96,6 +96,10 @@ impl Value {
         Value::Option(None)
     }
 
+    pub fn some(value: Value) -> Self {
+        Value::Option(Some(Box::new(value)))
+    }
+
     pub fn option(option: Option<Value>) -> Self {
         Value::Option(option.map(|value| Box::new(value)))
     }