The parts that make up the interpolated string, without the expressions that get inserted by interpolation.
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
.
IllegalArgumentException
if this is not the case.
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
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:
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 are left in the resulting
string literally. This is achieved by replacing each such occurrence by the
format specifier %%
.
IllegalArgumentException
if the number of parts
in the enclosing StringContext
does not exceed
the number of arguments arg
by exactly 1.
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).
The parts that make up the interpolated string, without the expressions that get inserted by interpolation.
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 = #
StringContext.InvalidEscapeException
if a parts
string contains a backslash (\
) character
that does not start a valid escape sequence.
IllegalArgumentException
if the number of parts
in the enclosing StringContext
does not exceed
the number of arguments arg
by exactly 1.
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
.
StringContext.InvalidEscapeException
if a parts
string contains a backslash (\
) character
that does not start a valid escape sequence.
IllegalArgumentException
if the number of parts
in the enclosing StringContext
does not exceed
the number of arguments arg
by exactly 1.
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:
s"Hello, $name"
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
extenion 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