This is an automated email from the ASF dual-hosted git repository.
joshtynjala pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/royale-docs.git
commit 9265524f6bbf0d8cdbef59523226f67f6dc9973b
Author: Josh Tynjala <joshtynj...@apache.org>
AuthorDate: Thu Aug 21 14:01:57 2025 -0700
null-conditional-operator and nullish-coalescing-operator
---
features/as3.md | 2 +
features/as3/null-conditional-operator.md | 51 ++++++++++++++++++++++++
features/as3/nullish-coalescing-operator.md | 62 +++++++++++++++++++++++++++++
3 files changed, 115 insertions(+)
diff --git a/features/as3.md b/features/as3.md
index 68c4b3d..8069e0c 100644
--- a/features/as3.md
+++ b/features/as3.md
@@ -66,6 +66,8 @@ The following new ActionScript features are available with
the Royale compiler:
* [Abstract Classes](features/as3/abstract-classes)
* [Import Aliases](features/as3/import-aliases)
+* [Null Conditional Operator](features/as3/null-conditional-operator)
+* [Nullish Coalescing Operator](features/as3/nullish-coalescing-operator)
* [Private Constructors](features/as3/private-constructors)
* [Type Inference](features/as3/type-inference)
* [Verbatim Strings](features/as3/verbatim-strings)
diff --git a/features/as3/null-conditional-operator.md
b/features/as3/null-conditional-operator.md
new file mode 100644
index 0000000..f661a8e
--- /dev/null
+++ b/features/as3/null-conditional-operator.md
@@ -0,0 +1,51 @@
+---
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements. See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You under the Apache License, Version 2.0
+# (the "License"); you may not use this file except in compliance with
+# the License. You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+layout: docpage
+title: Null conditional operator
+description: Null conditional operator in ActionScript
+permalink: /features/as3/null-conditional-operator
+---
+
+# Null conditional operator in ActionScript
+
+[Apache Royale](https://royale.apache.org/){:target='\_blank'} adds support
for the _null conditional operator_ in [ActionScript](features/as3), which uses
the symbol `?.`. The expression `a?.b` works similarly to a member access
expression, like `a.b`. The difference when using `?.` is that, if the left
operand is _nullish_, it will immediately return `null` instead of trying to
access the right operand and throwing an exception.
+
+The null conditional operator is also supported by the compiler included with
the Adobe AIR SDK starting with version 50.0.
+
+## Code example
+
+Consider the following code that uses the `?.` operator to access the field
`a` on the condition that the object is not nullish.
+
+```as3
+var obj:Object = null;
+var resolved:Object = obj?.a;
+trace(resolved); // null
+```
+
+If the expression `obj.a` were used instead of `obj?.a`, then an exception
would be thrown instead.
+
+If the object is not nullish, then it works similarly to regular member access.
+
+```as3
+var obj:Object = {a: 123.4};
+var resolved:Object = obj?.a;
+trace(resolved); // 123.4
+```
+
+## Limitations of the null conditional operator in Royale
+
+Other ActionScript compilers, such as the one in the [Apache Flex
SDK](https://flex.apache.org/){:target='_blank'}, may not recognize the null
conditional operator. Attemping to pass ActionScript or MXML source code that
contains null conditional operators to another compiler may result in
compile-time errors. In other words, to write 100% portable ActionScript code
that works with any compiler, avoid using null conditional operator and any of
Royale's other [extensions to the ActionScri [...]
diff --git a/features/as3/nullish-coalescing-operator.md
b/features/as3/nullish-coalescing-operator.md
new file mode 100644
index 0000000..8f0fc0c
--- /dev/null
+++ b/features/as3/nullish-coalescing-operator.md
@@ -0,0 +1,62 @@
+---
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements. See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You under the Apache License, Version 2.0
+# (the "License"); you may not use this file except in compliance with
+# the License. You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+layout: docpage
+title: Nullish coalescing operator
+description: Nullish coalescing operator in ActionScript
+permalink: /features/as3/nullish-coalescing-operator
+---
+
+# Nullish coalescing operator in ActionScript
+
+[Apache Royale](https://royale.apache.org/){:target='\_blank'} adds support
for the _nullish coalescing operator_ in [ActionScript](features/as3), which
uses the symbol `??`. The `??` operator accepts two operands, one each on its
left and right sides. Which operand is returned depends on whether the left
operand is _nullish_ or not.
+
+Nullish values include `null` and `undefined` only. If the left operand is not
nullish, then it is returned immediately, without executing the right operand.
If the left operand is nullish, then the right operand is returned instead.
+
+The nullish coalescing operator is also supported by the compiler included
with the Adobe AIR SDK starting with version 50.0.
+
+## Code example
+
+Consider the following code that uses the `??` operator to provide a non-null
value if the left operand is nullish.
+
+```as3
+var obj:Object = null;
+trace(obj == null); // true
+var resolved:Object = obj ?? {};
+trace(obj == null); // false
+```
+
+The next code shows that the left operand will be returned when it is not
nullish.
+
+```as3
+var obj:Object = {};
+var resolved:Object = obj ?? {};
+trace(resolved == obj); // true
+```
+
+The code below demonstrates the difference between `??` and `||` when
encountering a _falsy_ value.
+
+```as3
+var num:Number = 0;
+var checkNullish:Number = num ?? -1;
+var checkFalsy:Number = num || -1;
+trace(checkNullish == -1); // false
+trace(checkFalsy == -1); // true
+```
+
+## Limitations of the nullish coalescing operator in Royale
+
+Other ActionScript compilers, such as the one in the [Apache Flex
SDK](https://flex.apache.org/){:target='_blank'}, may not recognize the nullish
coalescing operator. Attemping to pass ActionScript or MXML source code that
contains nullish coalescing operators to another compiler may result in
compile-time errors. In other words, to write 100% portable ActionScript code
that works with any compiler, avoid using nullish coalescing operator and any
of Royale's other [extensions to the Acti [...]
