The parts that make up the interpolated string, without the expressions that get inserted by interpolation.
Test two objects for inequality.
true
if !(this == that), false otherwise.
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)
.
true
if the receiver object is equivalent to the argument; false
otherwise.
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
.
Checks that the length of the given argument args
is one less than the number of parts
supplied to the enclosing StringContext
.
IllegalArgumentException
if this is not the case.
Create a copy of the receiver object.
The default implementation of the clone
method is platform dependent.
a copy of the receiver object.
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
.For any non-null instance 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 formatted string interpolator.
It inserts its arguments between corresponding parts of the string context. It also treats standard escape sequences as defined in the Scala specification. Finally, if an interpolated expression is followed by a parts
string that starts with a formatting specifier, the expression is formatted according to that specifier. All specifiers allowed in Java format strings are handled, and in the same way they are treated in Java.
For example:
val height = 1.9d val name = "James" println(f"$name%s is $height%2.2f meters tall") // James is 1.90 meters tall
IllegalArgumentException
if the number of parts
in the enclosing StringContext
does not exceed the number of arguments arg
by exactly 1.
if a parts
string contains a backslash (\
) character that does not start a valid escape sequence. Note: The f
method works by assembling a format string from all the parts
strings and using java.lang.String.format
to format all arguments with that format string. The format string is obtained by concatenating all parts
strings, and performing two transformations:
parts
string except the first one. If a formatting position does not refer to a %
character (which is assumed to start a format specifier), then the string format specifier %s
is inserted. 2. Any %
characters not in formatting positions must begin one of the conversions %%
(the literal percent) or %n
(the platform-specific line separator).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
Returns string formatted according to given format
string. Format strings are as for String.format
(@see java.lang.String.format).
Returns the runtime class representation of the object.
a class object corresponding to the runtime type of the receiver.
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)
.
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.
not specified by SLS as a member of AnyRef
Wakes up all threads that are waiting on the receiver object's monitor.
not specified by SLS as a member of AnyRef
The raw string interpolator.
It inserts its arguments between corresponding parts of the string context. As opposed to the simple string interpolator s
, this one does not treat standard escape sequences as defined in the Scala specification.
For example, the raw processed string raw"a\nb"
is equal to the scala string "a\\nb"
.
Note: Even when using the raw interpolator, Scala will preprocess unicode escapes. For example:
scala> raw"\u0023" res0: String = #
IllegalArgumentException
if the number of parts
in the enclosing StringContext
does not exceed the number of arguments arg
by exactly 1.
The Scala compiler may replace a call to this method with an equivalent, but more efficient, use of a StringBuilder.
The simple string interpolator.
It inserts its arguments between corresponding parts of the string context. It also treats standard escape sequences as defined in the Scala specification. Here's an example of usage:
val name = "James" println(s"Hello, $name") // Hello, James
In this example, the expression $name is replaced with the toString
of the variable name
. The s
interpolator can take the toString
of any arbitrary expression within a ${}
block, for example:
println(s"1 + 1 = ${1 + 1}")
will print the string 1 + 1 = 2
.
IllegalArgumentException
if the number of parts
in the enclosing StringContext
does not exceed the number of arguments arg
by exactly 1.
StringContext.InvalidEscapeException
if a parts
string contains a backslash (\
) character that does not start a valid escape sequence.
The Scala compiler may replace a call to this method with an equivalent, but more efficient, use of a StringBuilder.
© 2002-2019 EPFL, with contributions from Lightbend.
Licensed under the Apache License, Version 2.0.
https://www.scala-lang.org/api/2.12.9/scala/StringContext.html
This class provides the basic mechanism to do String Interpolation. String Interpolation allows users to embed variable references directly in *processed* string literals. Here's an example:
Any processed string literal is rewritten as an instantiation and method call against this class. For example:
is rewritten to be:
By default, this class provides the
raw
,s
andf
methods as available interpolators.To provide your own string interpolator, create an implicit class which adds a method to
StringContext
. Here's an example:Here the
JsonHelper
extension class implicitly adds thejson
method toStringContext
which can be used forjson
string literals.The parts that make up the interpolated string, without the expressions that get inserted by interpolation.
2.10.0