scala

StringContext

case class StringContext(parts: String*) extends Product with Serializable

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:

val name = "James"
println(s"Hello, $name")  // Hello, James

Any processed string literal is rewritten as an instantiation and method call against this class. For example:

s"Hello, $name"

is rewritten to be:

StringContext("Hello, ", "").s(name)

By default, this class provides the raw, s and f methods as available interpolators.

To provide your own string interpolator, create an implicit class which adds a method to StringContext. Here's an example:

implicit class JsonHelper(val sc: StringContext) extends AnyVal {
  def json(args: Any*): JSONObject = ...
}
val x: JSONObject = json"{ a: $a }"

Here the JsonHelper extension class implicitly adds the json method to StringContext which can be used for json string literals.

parts

The parts that make up the interpolated string, without the expressions that get inserted by interpolation.

Source
StringContext.scala
Since

2.10.0

Linear Supertypes
Serializable, java.io.Serializable, Product, Equals, AnyRef, Any
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Inherited
  1. StringContext
  2. Serializable
  3. Serializable
  4. Product
  5. Equals
  6. AnyRef
  7. Any
Implicitly
  1. by any2stringadd
  2. by StringFormat
  3. by Ensuring
  4. by ArrowAssoc
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Visibility
  1. Public
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Instance Constructors

  1. new StringContext(parts: String*)

    parts

    The parts that make up the interpolated string, without the expressions that get inserted by interpolation.

Value Members

  1. final def !=(arg0: Any): Boolean

    Definition Classes
    AnyRef → Any
  2. final def ##(): Int

    Definition Classes
    AnyRef → Any
  3. def +(other: String): String

    Implicit information
    This member is added by an implicit conversion from StringContext to any2stringadd[StringContext] performed by method any2stringadd in scala.Predef.
    Definition Classes
    any2stringadd
  4. def ->[B](y: B): (StringContext, B)

    Implicit information
    This member is added by an implicit conversion from StringContext to ArrowAssoc[StringContext] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc
    Annotations
    @inline()
  5. final def ==(arg0: Any): Boolean

    Definition Classes
    AnyRef → Any
  6. final def asInstanceOf[T0]: T0

    Definition Classes
    Any
  7. def checkLengths(args: Seq[Any]): Unit

    Checks that the length of the given argument args is one less than the number of parts supplied to the enclosing StringContext.

    Checks that the length of the given argument args is one less than the number of parts supplied to the enclosing StringContext.

    Exceptions thrown
    An

    IllegalArgumentException if this is not the case.

  8. def clone(): AnyRef

    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  9. def ensuring(cond: (StringContext) ⇒ Boolean, msg: ⇒ Any): StringContext

    Implicit information
    This member is added by an implicit conversion from StringContext to Ensuring[StringContext] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  10. def ensuring(cond: (StringContext) ⇒ Boolean): StringContext

    Implicit information
    This member is added by an implicit conversion from StringContext to Ensuring[StringContext] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  11. def ensuring(cond: Boolean, msg: ⇒ Any): StringContext

    Implicit information
    This member is added by an implicit conversion from StringContext to Ensuring[StringContext] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  12. def ensuring(cond: Boolean): StringContext

    Implicit information
    This member is added by an implicit conversion from StringContext to Ensuring[StringContext] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  13. final def eq(arg0: AnyRef): Boolean

    Definition Classes
    AnyRef
  14. macro def f(args: Any*): String

    The formatted string interpolator.

    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
    Exceptions thrown
    A

    StringContext.InvalidEscapeException 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:

    1. Let a _formatting position_ be a start of any 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).

    An

    IllegalArgumentException if the number of parts in the enclosing StringContext does not exceed the number of arguments arg by exactly 1.

  15. def finalize(): Unit

    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( classOf[java.lang.Throwable] )
  16. def formatted(fmtstr: String): String

    Returns string formatted according to given format string.

    Returns string formatted according to given format string. Format strings are as for String.format (@see java.lang.String.format).

    Implicit information
    This member is added by an implicit conversion from StringContext to StringFormat[StringContext] performed by method StringFormat in scala.Predef.
    Definition Classes
    StringFormat
    Annotations
    @inline()
  17. final def getClass(): Class[_]

    Definition Classes
    AnyRef → Any
  18. final def isInstanceOf[T0]: Boolean

    Definition Classes
    Any
  19. final def ne(arg0: AnyRef): Boolean

    Definition Classes
    AnyRef
  20. final def notify(): Unit

    Definition Classes
    AnyRef
  21. final def notifyAll(): Unit

    Definition Classes
    AnyRef
  22. val parts: String*

    The parts that make up the interpolated string, without the expressions that get inserted by interpolation.

  23. def raw(args: Any*): String

    The raw string interpolator.

    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"\u0025"
    res0: String = #
    Exceptions thrown
    A

    StringContext.InvalidEscapeException if a parts string contains a backslash (\) character that does not start a valid escape sequence.

    An

    IllegalArgumentException if the number of parts in the enclosing StringContext does not exceed the number of arguments arg by exactly 1.

  24. def s(args: Any*): String

    The simple string interpolator.

    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.

    Exceptions thrown
    A

    StringContext.InvalidEscapeException if a parts string contains a backslash (\) character that does not start a valid escape sequence.

    An

    IllegalArgumentException if the number of parts in the enclosing StringContext does not exceed the number of arguments arg by exactly 1.

  25. def standardInterpolator(process: (String) ⇒ String, args: Seq[Any]): String

  26. final def synchronized[T0](arg0: ⇒ T0): T0

    Definition Classes
    AnyRef
  27. final def wait(): Unit

    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  28. final def wait(arg0: Long, arg1: Int): Unit

    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  29. final def wait(arg0: Long): Unit

    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  30. def [B](y: B): (StringContext, B)

    Implicit information
    This member is added by an implicit conversion from StringContext to ArrowAssoc[StringContext] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc

Inherited from Serializable

Inherited from java.io.Serializable

Inherited from Product

Inherited from Equals

Inherited from AnyRef

Inherited from Any

Inherited by implicit conversion any2stringadd from StringContext to any2stringadd[StringContext]

Inherited by implicit conversion StringFormat from StringContext to StringFormat[StringContext]

Inherited by implicit conversion Ensuring from StringContext to Ensuring[StringContext]

Inherited by implicit conversion ArrowAssoc from StringContext to ArrowAssoc[StringContext]

Ungrouped