# ScopedValue (JEP 506). Preview API in 21, final in 25.

$ javac ScopedValueDemo.java      (JDK 21, no flag)
    <repo>/lanes/src/ScopedValueDemo.java:9: error: ScopedValue is a preview API and is disabled by default.
        static final ScopedValue<String> CURRENT_USER = ScopedValue.newInstance();
                     ^
      (use --enable-preview to enable preview APIs)
    <repo>/lanes/src/ScopedValueDemo.java:9: error: ScopedValue is a preview API and is disabled by default.
        static final ScopedValue<String> CURRENT_USER = ScopedValue.newInstance();
                                                        ^
      (use --enable-preview to enable preview APIs)
    <repo>/lanes/src/ScopedValueDemo.java:13: error: ScopedValue is a preview API and is disabled by default.
            ScopedValue.where(CURRENT_USER, "ankur").run(() -> {
            ^
      (use --enable-preview to enable preview APIs)
    3 errors
    exit=1

$ javac ScopedValueDemo.java      (JDK 25, no flag)
    exit=0
$ java ScopedValueDemo      (JDK 25)
    java.version = 25.0.4.1
    CHECK ok   : inside the scope: CURRENT_USER.get() == ankur
    CHECK ok   : a method that was never passed the value still sees it
    CHECK ok   : outside the scope: CURRENT_USER.get() throws NoSuchElementException

$ javac ScopedValueDemo.java      (JDK 26, no flag)
    exit=0
$ java ScopedValueDemo      (JDK 26)
    java.version = 26.0.2.1
    CHECK ok   : inside the scope: CURRENT_USER.get() == ankur
    CHECK ok   : a method that was never passed the value still sees it
    CHECK ok   : outside the scope: CURRENT_USER.get() throws NoSuchElementException

$ javac ScopedValueDemo.java      (JDK 27, no flag)
    exit=0
$ java ScopedValueDemo      (JDK 27)
    java.version = 27
    CHECK ok   : inside the scope: CURRENT_USER.get() == ankur
    CHECK ok   : a method that was never passed the value still sees it
    CHECK ok   : outside the scope: CURRENT_USER.get() throws NoSuchElementException