The type of class symbols representing class and trait definitions.
The API of class symbols.
The API of class symbols. The main source of information about symbols is the Symbols page.
Class Symbol defines isXXX test methods such as isPublic or isFinal, params and
returnType methods for method symbols, baseClasses for class symbols and so on. Some of these methods don't
make sense for certain subclasses of Symbol and return NoSymbol, Nil or other empty values.
The type of method symbols representing def declarations.
The API of method symbols.
The API of method symbols. The main source of information about symbols is the Symbols page.
Class Symbol defines isXXX test methods such as isPublic or isFinal, params and
returnType methods for method symbols, baseClasses for class symbols and so on. Some of these methods don't
make sense for certain subclasses of Symbol and return NoSymbol, Nil or other empty values.
The type of module symbols representing object declarations.
The API of module symbols.
The API of module symbols. The main source of information about symbols is the Symbols page.
Class Symbol defines isXXX test methods such as isPublic or isFinal, params and
returnType methods for method symbols, baseClasses for class symbols and so on. Some of these methods don't
make sense for certain subclasses of Symbol and return NoSymbol, Nil or other empty values.
The type of symbols representing declarations.
The API of symbols.
The API of symbols. The main source of information about symbols is the Symbols page.
Class Symbol defines isXXX test methods such as isPublic or isFinal, params and
returnType methods for method symbols, baseClasses for class symbols and so on. Some of these methods don't
make sense for certain subclasses of Symbol and return NoSymbol, Nil or other empty values.
The type of term symbols representing val, var, def, and object declarations as well as packages and value parameters.
The API of term symbols.
The API of term symbols. The main source of information about symbols is the Symbols page.
Class Symbol defines isXXX test methods such as isPublic or isFinal, params and
returnType methods for method symbols, baseClasses for class symbols and so on. Some of these methods don't
make sense for certain subclasses of Symbol and return NoSymbol, Nil or other empty values.
The type of type symbols representing type, class, and trait declarations, as well as type parameters.
The API of type symbols.
The API of type symbols. The main source of information about symbols is the Symbols page.
Class Symbol defines isXXX test methods such as isPublic or isFinal, params and
returnType methods for method symbols, baseClasses for class symbols and so on. Some of these methods don't
make sense for certain subclasses of Symbol and return NoSymbol, Nil or other empty values.
A special "missing" symbol.
A special "missing" symbol. Commonly used in the API to denote a default or empty value.
Test two objects for inequality.
Test two objects for inequality.
true if !(this == that), false otherwise.
Equivalent to x.hashCode except for boxed numeric types and null.
Equivalent to x.hashCode except for boxed numeric types and null.
For numerics, it returns a hash value which is consistent
with value equality: if two value type instances compare
as true, then ## will produce the same hash value for each
of them.
For null returns a hashcode where null.hashCode throws a
NullPointerException.
a hash value consistent with ==
The expression x == that is equivalent to if (x eq null) that eq null else x.equals(that).
The expression x == that is equivalent to if (x eq null) that eq null else x.equals(that).
true if the receiver object is equivalent to the argument; false otherwise.
Cast the receiver object to be of type T0.
Cast the receiver object to be of type T0.
Note that the success of a cast at runtime is modulo Scala's erasure semantics.
Therefore the expression 1.asInstanceOf[String] will throw a ClassCastException at
runtime, while the expression List(1).asInstanceOf[List[String]] will not.
In the latter example, because the type argument is erased as part of compilation it is
not possible to check whether the contents of the list are of the requested type.
the receiver object.
ClassCastException if the receiver object is not an instance of the erasure of type T0.
Create a copy of the receiver object.
Create a copy of the receiver object.
The default implementation of the clone method is platform dependent.
a copy of the receiver object.
not specified by SLS as a member of AnyRef
Tests whether the argument (that) is a reference to the receiver object (this).
Tests whether the argument (that) is a reference to the receiver object (this).
The eq method implements an equivalence relation on
non-null instances of AnyRef, and has three additional properties:
x and y of type AnyRef, multiple invocations of
x.eq(y) consistently returns true or consistently returns false.x of type AnyRef, x.eq(null) and null.eq(x) returns false.null.eq(null) returns true. When overriding the equals or hashCode methods, it is important to ensure that their behavior is
consistent with reference equality. Therefore, if two objects are references to each other (o1 eq o2), they
should be equal to each other (o1 == o2) and they should hash to the same value (o1.hashCode == o2.hashCode).
true if the argument is a reference to the receiver object; false otherwise.
The equality method for reference types.
Called by the garbage collector on the receiver object when there are no more references to the object.
Called by the garbage collector on the receiver object when there are no more references to the object.
The details of when and if the finalize method is invoked, as
well as the interaction between finalize and non-local returns
and exceptions, are all platform dependent.
not specified by SLS as a member of AnyRef
A representation that corresponds to the dynamic class of the receiver object.
A representation that corresponds to the dynamic class of the receiver object.
The nature of the representation is platform dependent.
a representation that corresponds to the dynamic class of the receiver object.
not specified by SLS as a member of AnyRef
The hashCode method for reference types.
Test whether the dynamic type of the receiver object is T0.
Test whether the dynamic type of the receiver object is T0.
Note that the result of the test is modulo Scala's erasure semantics.
Therefore the expression 1.isInstanceOf[String] will return false, while the
expression List(1).isInstanceOf[List[String]] will return true.
In the latter example, because the type argument is erased as part of compilation it is
not possible to check whether the contents of the list are of the specified type.
true if the receiver object is an instance of erasure of type T0; false otherwise.
Equivalent to !(this eq that).
Equivalent to !(this eq that).
true if the argument is not a reference to the receiver object; false otherwise.
Wakes up a single thread that is waiting on the receiver object's monitor.
Wakes up a single thread that is waiting on the receiver object's monitor.
not specified by SLS as a member of AnyRef
Wakes up all threads that are waiting on the receiver object's monitor.
Wakes up all threads that are waiting on the receiver object's monitor.
not specified by SLS as a member of AnyRef
Creates a String representation of this object.
Creates a String representation of this object. The default representation is platform dependent. On the java platform it is the concatenation of the class name, "@", and the object's hashcode in hexadecimal.
a String representation of the object.
The methods available for each reflection entity, without the implementation. Since the reflection entities are later overridden by runtime reflection and macros, their API counterparts guarantee a minimum set of methods that are implemented.
EXPERIMENTAL
This trait defines symbols and operations on them.
Symbols are used to establish bindings between a name and the entity it refers to, such as a class or a method. Anything you define and can give a name to in Scala has an associated symbol.
Symbols contain all available information about the declaration of an entity (class/object/trait etc.) or a member (vals/vars/defs etc.), and as such are an integral abstraction central to both runtime reflection and macros.
A symbol can provide a wealth of information ranging from the basic
namemethod available on all symbols to other, more involved, concepts such as getting thebaseClassesfromClassSymbol. Other common use cases of symbols include inspecting members' signatures, getting type parameters of a class, getting the parameter type of a method or finding out the type of a field.Example usage of runtime reflection; getting a method's type signature:
Symbols are organized in a hierarchy. For example, a symbol that represents a parameter of a method is owned by the corresponding method symbol, a method symbol is owned by its enclosing class, a class is owned by a containing package and so on.
Certain types of tree nodes, such as Ident (references to identifiers) and Select (references to members) expose method
symbolto obtain the symbol that represents their declaration. During the typechecking phase, the compiler looks up the symbol based on the name and scope and sets thesymbolfield of tree nodes.For more information about
Symbolusage and attached intricacies, see the Reflection Guide: Symbols