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, JamesAny 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 theraw,s andf methods as available interpolators.
To provide your own string interpolator, create an implicit class which adds a method toStringContext. Here's an example:
implicit class JsonHelper(private val sc: StringContext) extends AnyVal { def json(args: Any*): JSONObject = ...}val x: JSONObject = json"{ a: $a }"Here theJsonHelper extension class implicitly adds thejson method toStringContext which can be used forjson string literals.
Value parameters
- parts
The parts that make up the interpolated string, without the expressions that get inserted by interpolation.
Attributes
- Companion
- object
- Source
- StringContext.scala
- Graph
- Supertypes
Members list
Type members
Classlikes
Attributes
- Source
- StringContext.scala
- Supertypes
- Self type
Value members
Concrete methods
The formatted string interpolator.
The formatted string interpolator.
It inserts its arguments between corresponding parts of the string context. It also treats standard escape sequences as defined in the Scala specification. Finally, if an interpolated expression is followed by aparts string that starts with a formatting specifier, the expression is formatted according to that specifier. All specifiers allowed in Java format strings are handled, and in the same way they are treated in Java.
For example:
val height = 1.9dval name = "James"println(f"$name%s is $height%2.2f meters tall") // James is 1.90 meters tallValue parameters
- `args`
The arguments to be inserted into the resulting string.
Attributes
- Throws
IllegalArgumentException if the number of
partsin the enclosingStringContextdoes not exceed the number of argumentsargby exactly 1.if a
partsstring contains a backslash (\) character that does not start a valid escape sequence. Note: Thefmethod works by assembling a format string from all thepartsstrings and usingjava.lang.String.formatto format all arguments with that format string. The format string is obtained by concatenating allpartsstrings, and performing two transformations:Let a _formatting position_ be a start of any
partsstring 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%sis inserted. 2. Any%characters not in formatting positions must begin one of the conversions%%(the literal percent) or%n(the platform-specific line separator).
- Source
- StringContext.scala
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 interpolators, this one does not treat standard escape sequences as defined in the Scala specification.
For example, the raw processed stringraw"a\nb" is equal to the scala string"a\\nb".
Note: Even when using the raw interpolator, Scala will process Unicode escapes. Unicode processing in the raw interpolator is deprecated as of scala 2.13.2 and will be removed in the future For example:
scala> raw"\u005cu0023"res0: String = #Value parameters
- `args`
The arguments to be inserted into the resulting string.
Attributes
- Throws
IllegalArgumentException if the number of
partsin the enclosingStringContextdoes not exceed the number of argumentsargby exactly 1.- Note
The Scala compiler may replace a call to this method with an equivalent, but more efficient, use of a StringBuilder.
- Source
- StringContext.scala
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, JamesIn this example, the expression $name is replaced with thetoString of the variablename. Thes interpolator can take thetoString of any arbitrary expression within a${} block, for example:
println(s"1 + 1 = ${1 + 1}")will print the string1 + 1 = 2.
Value parameters
- `args`
The arguments to be inserted into the resulting string.
Attributes
- Throws
IllegalArgumentException if the number of
partsin the enclosingStringContextdoes not exceed the number of argumentsargby exactly 1.StringContext.InvalidEscapeException if a
partsstring contains a backslash (\) character that does not start a valid escape sequence.- Note
The Scala compiler may replace a call to this method with an equivalent, but more efficient, use of a StringBuilder.
- Source
- StringContext.scala
Deprecated methods
Attributes
- Deprecated
[Since version 2.13.0]use same-named method on StringContext companion object- Source
- StringContext.scala
Attributes
- Deprecated
[Since version 2.13.0]Use the static method StringContext.standardInterpolator instead of the instance method- Source
- StringContext.scala
Inherited methods
An iterator over the names of all the elements of this product.
An iterator over the names of all the elements of this product.
Attributes
- Inherited from:
- Product
- Source
- Product.scala
An iterator over all the elements of this product.
An iterator over all the elements of this product.
Attributes
- Returns
in the default implementation, an
Iterator[Any]- Inherited from:
- Product
- Source
- Product.scala