Add is_shared function.

src/engine.rs

@@ -99,6 +99,7 @@ pub const KEYWORD_FN_PTR_CALL: &str = "call";
 pub const KEYWORD_FN_PTR_CURRY: &str = "curry";
 pub const KEYWORD_SHARED: &str = "shared";
 pub const KEYWORD_TAKE: &str = "take";
+pub const KEYWORD_IS_SHARED: &str = "is_shared";
 pub const KEYWORD_THIS: &str = "this";
 pub const FN_TO_STRING: &str = "to_string";
 #[cfg(not(feature = "no_object"))]
@@ -181,10 +182,10 @@ impl Target<'_> {
     /// Get the value of the `Target` as a `Dynamic`, cloning a referenced value if necessary.
     pub fn clone_into_dynamic(self) -> Dynamic {
         match self {
-            Self::Ref(r) => r.clone(),          // Referenced value is cloned
+            Self::Ref(r) => r.clone(), // Referenced value is cloned
             #[cfg(not(feature = "no_shared"))]
             Self::LockGuard((_, orig)) => orig, // Original value is simply taken
-            Self::Value(v) => v,                // Owned value is simply taken
+            Self::Value(v) => v,       // Owned value is simply taken
             #[cfg(not(feature = "no_index"))]
             Self::StringChar(_, _, ch) => ch, // Character is taken
         }

src/fn_call.rs

@@ -4,8 +4,8 @@ use crate::any::Dynamic;
 use crate::calc_fn_hash;
 use crate::engine::{
     search_imports, search_namespace, search_scope_only, Engine, Imports, State, KEYWORD_DEBUG,
-    KEYWORD_EVAL, KEYWORD_FN_PTR, KEYWORD_FN_PTR_CALL, KEYWORD_FN_PTR_CURRY, KEYWORD_PRINT,
-    KEYWORD_SHARED, KEYWORD_TAKE, KEYWORD_TYPE_OF,
+    KEYWORD_EVAL, KEYWORD_FN_PTR, KEYWORD_FN_PTR_CALL, KEYWORD_FN_PTR_CURRY, KEYWORD_IS_SHARED,
+    KEYWORD_PRINT, KEYWORD_SHARED, KEYWORD_TAKE, KEYWORD_TYPE_OF,
 };
 use crate::error::ParseErrorType;
 use crate::fn_native::{FnCallArgs, FnPtr};
@@ -451,6 +451,12 @@ impl Engine {
                 )))
             }
 
+            // Fn
+            KEYWORD_IS_SHARED if args.len() == 1 => Err(Box::new(EvalAltResult::ErrorRuntime(
+                "'is_shared' should not be called in method style. Try is_shared(...);".into(),
+                Position::none(),
+            ))),
+
             // eval - reaching this point it must be a method-style call
             KEYWORD_EVAL
                 if args.len() == 1 && !self.has_override(lib, hash_fn, hash_script, pub_only) =>
@@ -783,6 +789,15 @@ impl Engine {
             .into());
         }
 
+        // Handle is_shared()
+        #[cfg(not(feature = "no_shared"))]
+        if name == KEYWORD_IS_SHARED && args_expr.len() == 1 {
+            let expr = args_expr.get(0).unwrap();
+            let value = self.eval_expr(scope, mods, state, lib, this_ptr, expr, level)?;
+
+            return Ok(value.is_shared().into());
+        }
+
         // Handle shared()
         #[cfg(not(feature = "no_shared"))]
         if name == KEYWORD_SHARED && args_expr.len() == 1 {

src/token.rs

@@ -2,7 +2,7 @@
 
 use crate::engine::{
     Engine, KEYWORD_DEBUG, KEYWORD_EVAL, KEYWORD_FN_PTR, KEYWORD_FN_PTR_CALL, KEYWORD_FN_PTR_CURRY,
-    KEYWORD_PRINT, KEYWORD_SHARED, KEYWORD_TAKE, KEYWORD_THIS, KEYWORD_TYPE_OF,
+    KEYWORD_IS_SHARED, KEYWORD_PRINT, KEYWORD_SHARED, KEYWORD_TAKE, KEYWORD_THIS, KEYWORD_TYPE_OF,
 };
 
 use crate::error::LexError;
@@ -1431,28 +1431,22 @@ fn get_identifier(
 /// Is this keyword allowed as a function?
 #[inline(always)]
 pub fn is_keyword_function(name: &str) -> bool {
-    #[cfg(not(feature = "no_shared"))]
-    if name == KEYWORD_SHARED || name == KEYWORD_TAKE {
-        return true;
+    match name {
+        #[cfg(not(feature = "no_shared"))]
+        KEYWORD_SHARED | KEYWORD_TAKE | KEYWORD_IS_SHARED => true,
+        KEYWORD_PRINT | KEYWORD_DEBUG | KEYWORD_TYPE_OF | KEYWORD_EVAL | KEYWORD_FN_PTR
+        | KEYWORD_FN_PTR_CALL | KEYWORD_FN_PTR_CURRY => true,
+        _ => false,
     }
-
-    name == KEYWORD_PRINT
-        || name == KEYWORD_DEBUG
-        || name == KEYWORD_TYPE_OF
-        || name == KEYWORD_EVAL
-        || name == KEYWORD_FN_PTR
-        || name == KEYWORD_FN_PTR_CALL
-        || name == KEYWORD_FN_PTR_CURRY
 }
 
 /// Can this keyword be overridden as a function?
 #[inline(always)]
 pub fn can_override_keyword(name: &str) -> bool {
-    name == KEYWORD_PRINT
-        || name == KEYWORD_DEBUG
-        || name == KEYWORD_TYPE_OF
-        || name == KEYWORD_EVAL
-        || name == KEYWORD_FN_PTR
+    match name {
+        KEYWORD_PRINT | KEYWORD_DEBUG | KEYWORD_TYPE_OF | KEYWORD_EVAL | KEYWORD_FN_PTR => true,
+        _ => false,
+    }
 }
 
 pub fn is_valid_identifier(name: impl Iterator<Item = char>) -> bool {