class Regex extends Serializable
A regular expression is used to determine whether a string matches a pattern and, if it does, to extract or transform the parts that match.
Usage
This class delegates to the java.util.regex package of the Java Platform. See the documentation for java.util.regex.Pattern for details about the regular expression syntax for pattern strings.
An instance of Regex
represents a compiled regular expression pattern.
Since compilation is expensive, frequently used Regex
es should be constructed
once, outside of loops and perhaps in a companion object.
The canonical way to create a Regex
is by using the method r
, provided
implicitly for strings:
val date = """(\d\d\d\d)-(\d\d)-(\d\d)""".r
Since escapes are not processed in multi-line string literals, using triple quotes
avoids having to escape the backslash character, so that "\\d"
can be written """\d"""
.
Extraction
To extract the capturing groups when a Regex
is matched, use it as
an extractor in a pattern match:
"2004-01-20" match { case date(year, month, day) => s"$year was a good year for PLs." }
To check only whether the Regex
matches, ignoring any groups,
use a sequence wildcard:
"2004-01-20" match { case date(_*) => "It's a date!" }
That works because a Regex
extractor produces a sequence of strings.
Extracting only the year from a date could also be expressed with
a sequence wildcard:
"2004-01-20" match { case date(year, _*) => s"$year was a good year for PLs." }
In a pattern match, Regex
normally matches the entire input.
However, an unanchored Regex
finds the pattern anywhere
in the input.
val embeddedDate = date.unanchored "Date: 2004-01-20 17:25:18 GMT (10 years, 28 weeks, 5 days, 17 hours and 51 minutes ago)" match { case embeddedDate("2004", "01", "20") => "A Scala is born." }
Find Matches
To find or replace matches of the pattern, use the various find and replace methods.
For each method, there is a version for working with matched strings and
another for working with Match
objects.
For example, pattern matching with an unanchored Regex
, as in the previous example,
can also be accomplished using findFirstMatchIn
. The findFirst
methods return an Option
which is non-empty if a match is found, or None
for no match:
val dates = "Important dates in history: 2004-01-20, 1958-09-05, 2010-10-06, 2011-07-15" val firstDate = date.findFirstIn(dates).getOrElse("No date found.") val firstYear = for (m <- date.findFirstMatchIn(dates)) yield m.group(1)
To find all matches:
val allYears = for (m <- date.findAllMatchIn(dates)) yield m.group(1)
To iterate over the matched strings, use findAllIn
, which returns a special iterator
that can be queried for the MatchData
of the last match:
val mi = date.findAllIn(dates) while (mi.hasNext) { val d = mi.next if (mi.group(1).toInt < 1960) println(s"$d: An oldie but goodie.")
Note that findAllIn
finds matches that don't overlap. (See findAllIn for more examples.)
val num = """(\d+)""".r val all = num.findAllIn("123").toList // List("123"), not List("123", "23", "3")
Also, the "current match" of a MatchIterator
may be advanced by either hasNext
or next
.
By comparison, the Iterator[Match]
returned by findAllMatchIn
or findAllIn.matchData
produces Match
objects that remain valid after the iterator is advanced.
val ns = num.findAllIn("1 2 3") ns.start // 0 ns.hasNext // true ns.start // 2 val ms = num.findAllMatchIn("1 2 3") val m = ms.next() m.start // 0 ms.hasNext // true m.start // still 0
Replace Text
Text replacement can be performed unconditionally or as a function of the current match:
val redacted = date.replaceAllIn(dates, "XXXX-XX-XX") val yearsOnly = date.replaceAllIn(dates, m => m.group(1)) val months = (0 to 11).map { i => val c = Calendar.getInstance; c.set(2014, i, 1); f"$c%tb" } val reformatted = date.replaceAllIn(dates, _ match { case date(y,m,d) => f"${months(m.toInt - 1)} $d, $y" })
Pattern matching the Match
against the Regex
that created it does not reapply the Regex
.
In the expression for reformatted
, each date
match is computed once. But it is possible to apply a
Regex
to a Match
resulting from a different pattern:
val docSpree = """2011(?:-\d{2}){2}""".r val docView = date.replaceAllIn(dates, _ match { case docSpree() => "Historic doc spree!" case _ => "Something else happened" })
- Self Type
- Regex
- Annotations
- @SerialVersionUID()
- Source
- Regex.scala
- Version
1.1, 29/01/2008
- See also
java.util.regex.Pattern
- Alphabetic
- By Inheritance
- Regex
- Serializable
- Serializable
- AnyRef
- Any
- by any2stringadd
- by StringFormat
- by Ensuring
- by ArrowAssoc
- Hide All
- Show All
- Public
- All
Instance Constructors
-
new
Regex(regex: String, groupNames: String*)
Compile a regular expression, supplied as a string, into a pattern that can be matched against inputs.
Compile a regular expression, supplied as a string, into a pattern that can be matched against inputs.
If group names are supplied, they can be used this way:
val namedDate = new Regex("""(\d\d\d\d)-(\d\d)-(\d\d)""", "year", "month", "day") val namedYears = for (m <- namedDate findAllMatchIn dates) yield m group "year"
Group names supplied to the constructor are preferred to inline group names when retrieving matched groups by name. Not all platforms support inline names.
This constructor does not support options as flags, which must be supplied as inline flags in the pattern string:
(?idmsux-idmsux)
.- regex
The regular expression to compile.
- groupNames
Names of capturing groups.
Value Members
-
final
def
!=(arg0: Any): Boolean
Test two objects for inequality.
Test two objects for inequality.
- returns
true
if !(this == that), false otherwise.
- Definition Classes
- AnyRef → Any
-
final
def
##(): Int
Equivalent to
x.hashCode
except for boxed numeric types andnull
.Equivalent to
x.hashCode
except for boxed numeric types andnull
. 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. Fornull
returns a hashcode wherenull.hashCode
throws aNullPointerException
.- returns
a hash value consistent with ==
- Definition Classes
- AnyRef → Any
-
def
+(other: String): String
- Implicit
- This member is added by an implicit conversion from Regex to any2stringadd[Regex] performed by method any2stringadd in scala.Predef.
- Definition Classes
- any2stringadd
-
def
->[B](y: B): (Regex, B)
- Implicit
- This member is added by an implicit conversion from Regex to ArrowAssoc[Regex] performed by method ArrowAssoc in scala.Predef.
- Definition Classes
- ArrowAssoc
- Annotations
- @inline()
-
final
def
==(arg0: Any): Boolean
The expression
x == that
is equivalent toif (x eq null) that eq null else x.equals(that)
.The expression
x == that
is equivalent toif (x eq null) that eq null else x.equals(that)
.- returns
true
if the receiver object is equivalent to the argument;false
otherwise.
- Definition Classes
- AnyRef → Any
- def anchored: Regex
-
final
def
asInstanceOf[T0]: T0
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 aClassCastException
at runtime, while the expressionList(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.- returns
the receiver object.
- Definition Classes
- Any
- Exceptions thrown
ClassCastException
if the receiver object is not an instance of the erasure of typeT0
.
-
def
clone(): AnyRef
Create a copy of the receiver object.
-
def
ensuring(cond: (Regex) ⇒ Boolean, msg: ⇒ Any): Regex
- Implicit
- This member is added by an implicit conversion from Regex to Ensuring[Regex] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
-
def
ensuring(cond: (Regex) ⇒ Boolean): Regex
- Implicit
- This member is added by an implicit conversion from Regex to Ensuring[Regex] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
-
def
ensuring(cond: Boolean, msg: ⇒ Any): Regex
- Implicit
- This member is added by an implicit conversion from Regex to Ensuring[Regex] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
-
def
ensuring(cond: Boolean): Regex
- Implicit
- This member is added by an implicit conversion from Regex to Ensuring[Regex] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
-
final
def
eq(arg0: AnyRef): Boolean
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 ofAnyRef
, and has three additional properties:- It is consistent: for any non-null instances
x
andy
of typeAnyRef
, multiple invocations ofx.eq(y)
consistently returnstrue
or consistently returnsfalse
. - For any non-null instance
x
of typeAnyRef
,x.eq(null)
andnull.eq(x)
returnsfalse
. null.eq(null)
returnstrue
.
When overriding the
equals
orhashCode
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
).- returns
true
if the argument is a reference to the receiver object;false
otherwise.
- Definition Classes
- AnyRef
- It is consistent: for any non-null instances
-
def
equals(arg0: Any): Boolean
The equality method for reference types.
-
def
finalize(): Unit
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 betweenfinalize
and non-local returns and exceptions, are all platform dependent. -
def
findAllIn(source: CharSequence): MatchIterator
Return all non-overlapping matches of this
Regex
in the given character sequence as a scala.util.matching.Regex.MatchIterator, which is a special scala.collection.Iterator that returns the matched strings but can also be queried for more data about the last match, such as capturing groups and start position.Return all non-overlapping matches of this
Regex
in the given character sequence as a scala.util.matching.Regex.MatchIterator, which is a special scala.collection.Iterator that returns the matched strings but can also be queried for more data about the last match, such as capturing groups and start position.A
MatchIterator
can also be converted into an iterator that returns objects of type scala.util.matching.Regex.Match, such as is normally returned byfindAllMatchIn
.Where potential matches overlap, the first possible match is returned, followed by the next match that follows the input consumed by the first match:
val hat = "hat[^a]+".r val hathaway = "hathatthattthatttt" val hats = hat.findAllIn(hathaway).toList // List(hath, hattth) val pos = hat.findAllMatchIn(hathaway).map(_.start).toList // List(0, 7)
To return overlapping matches, it is possible to formulate a regular expression with lookahead (
?=
) that does not consume the overlapping region.val madhatter = "(h)(?=(at[^a]+))".r val madhats = madhatter.findAllMatchIn(hathaway).map { case madhatter(x,y) => s"$x$y" }.toList // List(hath, hatth, hattth, hatttt)
Attempting to retrieve match information after exhausting the iterator results in java.lang.IllegalStateException. See scala.util.matching.Regex.MatchIterator for details.
- source
The text to match against.
- returns
A scala.util.matching.Regex.MatchIterator of matched substrings.
for (words <- """\w+""".r findAllIn "A simple example.") yield words
Example: -
def
findAllMatchIn(source: CharSequence): Iterator[Match]
Return all non-overlapping matches of this regexp in given character sequence as a scala.collection.Iterator of scala.util.matching.Regex.Match.
Return all non-overlapping matches of this regexp in given character sequence as a scala.collection.Iterator of scala.util.matching.Regex.Match.
- source
The text to match against.
- returns
A scala.collection.Iterator of scala.util.matching.Regex.Match for all matches.
for (words <- """\w+""".r findAllMatchIn "A simple example.") yield words.start
Example: -
def
findFirstIn(source: CharSequence): Option[String]
Return an optional first matching string of this
Regex
in the given character sequence, or None if there is no match.Return an optional first matching string of this
Regex
in the given character sequence, or None if there is no match.- source
The text to match against.
- returns
An scala.Option of the first matching string in the text.
"""\w+""".r findFirstIn "A simple example." foreach println // prints "A"
Example: -
def
findFirstMatchIn(source: CharSequence): Option[Match]
Return an optional first match of this
Regex
in the given character sequence, or None if it does not exist.Return an optional first match of this
Regex
in the given character sequence, or None if it does not exist.If the match is successful, the scala.util.matching.Regex.Match can be queried for more data.
- source
The text to match against.
- returns
A scala.Option of scala.util.matching.Regex.Match of the first matching string in the text.
("""[a-z]""".r findFirstMatchIn "A simple example.") map (_.start) // returns Some(2), the index of the first match in the text
Example: -
def
findPrefixMatchOf(source: CharSequence): Option[Match]
Return an optional match of this
Regex
at the beginning of the given character sequence, or None if it matches no prefix of the character sequence.Return an optional match of this
Regex
at the beginning of the given character sequence, or None if it matches no prefix of the character sequence.Unlike
findFirstMatchIn
, this method will only return a match at the beginning of the input.- source
The text to match against.
- returns
A scala.Option of the scala.util.matching.Regex.Match of the matched string.
"""\w+""".r findPrefixMatchOf "A simple example." map (_.after) // returns Some(" simple example.")
Example: -
def
findPrefixOf(source: CharSequence): Option[String]
Return an optional match of this
Regex
at the beginning of the given character sequence, or None if it matches no prefix of the character sequence.Return an optional match of this
Regex
at the beginning of the given character sequence, or None if it matches no prefix of the character sequence.Unlike
findFirstIn
, this method will only return a match at the beginning of the input.- source
The text to match against.
- returns
A scala.Option of the matched prefix.
"""\p{Lower}""".r findPrefixOf "A simple example." // returns None, since the text does not begin with a lowercase letter
Example: -
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 forString.format
(@see java.lang.String.format).- Implicit
- This member is added by an implicit conversion from Regex to StringFormat[Regex] performed by method StringFormat in scala.Predef.
- Definition Classes
- StringFormat
- Annotations
- @inline()
-
final
def
getClass(): Class[_]
Returns the runtime class representation of the object.
Returns the runtime class representation of the object.
- returns
a class object corresponding to the runtime type of the receiver.
- Definition Classes
- AnyRef → Any
-
def
hashCode(): Int
The hashCode method for reference types.
-
final
def
isInstanceOf[T0]: Boolean
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 returnfalse
, while the expressionList(1).isInstanceOf[List[String]]
will returntrue
. 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.- returns
true
if the receiver object is an instance of erasure of typeT0
;false
otherwise.
- Definition Classes
- Any
-
final
def
ne(arg0: AnyRef): Boolean
Equivalent to
!(this eq that)
.Equivalent to
!(this eq that)
.- returns
true
if the argument is not a reference to the receiver object;false
otherwise.
- Definition Classes
- AnyRef
-
final
def
notify(): Unit
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.
- Definition Classes
- AnyRef
- Note
not specified by SLS as a member of AnyRef
-
final
def
notifyAll(): Unit
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.
- Definition Classes
- AnyRef
- Note
not specified by SLS as a member of AnyRef
- val pattern: Pattern
- def regex: String
-
def
replaceAllIn(target: CharSequence, replacer: (Match) ⇒ String): String
Replaces all matches using a replacer function.
Replaces all matches using a replacer function. The replacer function takes a scala.util.matching.Regex.Match so that extra information can be obtained from the match. For example:
import scala.util.matching.Regex val datePattern = new Regex("""(\d\d\d\d)-(\d\d)-(\d\d)""", "year", "month", "day") val text = "From 2011-07-15 to 2011-07-17" val repl = datePattern replaceAllIn (text, m => s"${m group "month"}/${m group "day"}")
In the replacement String, a dollar sign (
$
) followed by a number will be interpreted as a reference to a group in the matched pattern, with numbers 1 through 9 corresponding to the first nine groups, and 0 standing for the whole match. Any other character is an error. The backslash (\
) character will be interpreted as an escape character and can be used to escape the dollar sign. UseRegex.quoteReplacement
to escape these characters.- target
The string to match.
- replacer
The function which maps a match to another string.
- returns
The target string after replacements.
-
def
replaceAllIn(target: CharSequence, replacement: String): String
Replaces all matches by a string.
Replaces all matches by a string.
In the replacement String, a dollar sign (
$
) followed by a number will be interpreted as a reference to a group in the matched pattern, with numbers 1 through 9 corresponding to the first nine groups, and 0 standing for the whole match. Any other character is an error. The backslash (\
) character will be interpreted as an escape character and can be used to escape the dollar sign. UseRegex.quoteReplacement
to escape these characters.- target
The string to match
- replacement
The string that will replace each match
- returns
The resulting string
"""\d+""".r replaceAllIn ("July 15", "
" ) // returns "July"
Example: -
def
replaceFirstIn(target: CharSequence, replacement: String): String
Replaces the first match by a string.
Replaces the first match by a string.
In the replacement String, a dollar sign (
$
) followed by a number will be interpreted as a reference to a group in the matched pattern, with numbers 1 through 9 corresponding to the first nine groups, and 0 standing for the whole match. Any other character is an error. The backslash (\
) character will be interpreted as an escape character and can be used to escape the dollar sign. UseRegex.quoteReplacement
to escape these characters.- target
The string to match
- replacement
The string that will replace the match
- returns
The resulting string
-
def
replaceSomeIn(target: CharSequence, replacer: (Match) ⇒ Option[String]): String
Replaces some of the matches using a replacer function that returns an scala.Option.
Replaces some of the matches using a replacer function that returns an scala.Option. The replacer function takes a scala.util.matching.Regex.Match so that extra information can be obtained from the match. For example:
import scala.util.matching.Regex._ val vars = Map("x" -> "a var", "y" -> """some $ and \ signs""") val text = "A text with variables %x, %y and %z." val varPattern = """%(\w+)""".r val mapper = (m: Match) => vars get (m group 1) map (quoteReplacement(_)) val repl = varPattern replaceSomeIn (text, mapper)
In the replacement String, a dollar sign (
$
) followed by a number will be interpreted as a reference to a group in the matched pattern, with numbers 1 through 9 corresponding to the first nine groups, and 0 standing for the whole match. Any other character is an error. The backslash (\
) character will be interpreted as an escape character and can be used to escape the dollar sign. UseRegex.quoteReplacement
to escape these characters.- target
The string to match.
- replacer
The function which optionally maps a match to another string.
- returns
The target string after replacements.
-
def
runMatcher(m: Matcher): Boolean
- Attributes
- protected
-
def
split(toSplit: CharSequence): Array[String]
Splits the provided character sequence around matches of this regexp.
Splits the provided character sequence around matches of this regexp.
- toSplit
The character sequence to split
- returns
The array of strings computed by splitting the input around matches of this regexp
-
final
def
synchronized[T0](arg0: ⇒ T0): T0
- Definition Classes
- AnyRef
-
def
toString(): String
The string defining the regular expression
-
def
unanchored: UnanchoredRegex
Create a new Regex with the same pattern, but no requirement that the entire String matches in extractor patterns.
Create a new Regex with the same pattern, but no requirement that the entire String matches in extractor patterns.
Normally, matching on
date
behaves as though the pattern were enclosed in anchors,"^pattern$"
.
The unanchored
Regex
behaves as though those anchors were removed.Note that this method does not actually strip any matchers from the pattern.
Calling
anchored
returns the originalRegex
.val date = """(\d\d\d\d)-(\d\d)-(\d\d)""".r.unanchored val date(year, month, day) = "Date 2011-07-15" // OK val copyright: String = "Date of this document: 2011-07-15" match { case date(year, month, day) => s"Copyright $year" // OK case _ => "No copyright" }
- returns
The new unanchored regex
-
def
unapplySeq(m: Match): Option[List[String]]
Tries to match on a scala.util.matching.Regex.Match.
Tries to match on a scala.util.matching.Regex.Match.
A previously failed match results in None.
If a successful match was made against the current pattern, then that result is used.
Otherwise, this Regex is applied to the previously matched input, and the result of that match is used.
-
def
unapplySeq(c: Char): Option[List[Char]]
Tries to match the String representation of a scala.Char.
Tries to match the String representation of a scala.Char.
If the match succeeds, the result is the first matching group if any groups are defined, or an empty Sequence otherwise.
For example:
val cat = "cat" // the case must consume the group to match val r = """(\p{Lower})""".r cat(0) match { case r(x) => true } cat(0) match { case r(_) => true } cat(0) match { case r(_*) => true } cat(0) match { case r() => true } // no match // there is no group to extract val r = """\p{Lower}""".r cat(0) match { case r(x) => true } // no match cat(0) match { case r(_) => true } // no match cat(0) match { case r(_*) => true } // matches cat(0) match { case r() => true } // matches // even if there are multiple groups, only one is returned val r = """((.))""".r cat(0) match { case r(_) => true } // matches cat(0) match { case r(_,_) => true } // no match
- c
The Char to match
- returns
The match
-
def
unapplySeq(s: CharSequence): Option[List[String]]
Tries to match a java.lang.CharSequence.
Tries to match a java.lang.CharSequence.
If the match succeeds, the result is a list of the matching groups (or a
null
element if a group did not match any input). If the pattern specifies no groups, then the result will be an empty list on a successful match.This method attempts to match the entire input by default; to find the next matching subsequence, use an unanchored
Regex
.For example:
val p1 = "ab*c".r val p1Matches = "abbbc" match { case p1() => true // no groups case _ => false } val p2 = "a(b*)c".r val p2Matches = "abbbc" match { case p2(_*) => true // any groups case _ => false } val numberOfB = "abbbc" match { case p2(b) => Some(b.length) // one group case _ => None } val p3 = "b*".r.unanchored val p3Matches = "abbbc" match { case p3() => true // find the b's case _ => false } val p4 = "a(b*)(c+)".r val p4Matches = "abbbcc" match { case p4(_*) => true // multiple groups case _ => false } val allGroups = "abbbcc" match { case p4(all @ _*) => all mkString "/" // "bbb/cc" case _ => "" } val cGroup = "abbbcc" match { case p4(_, c) => c case _ => "" }
- s
The string to match
- returns
The matches
-
final
def
wait(): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws( ... )
-
final
def
wait(arg0: Long, arg1: Int): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws( ... )
-
final
def
wait(arg0: Long): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws( ... )
-
def
→[B](y: B): (Regex, B)
- Implicit
- This member is added by an implicit conversion from Regex to ArrowAssoc[Regex] performed by method ArrowAssoc in scala.Predef.
- Definition Classes
- ArrowAssoc
This is the documentation for the Scala standard library.
Package structure
The scala package contains core types like
Int
,Float
,Array
orOption
which are accessible in all Scala compilation units without explicit qualification or imports.Notable packages include:
scala.collection
and its sub-packages contain Scala's collections frameworkscala.collection.immutable
- Immutable, sequential data-structures such asVector
,List
,Range
,HashMap
orHashSet
scala.collection.mutable
- Mutable, sequential data-structures such asArrayBuffer
,StringBuilder
,HashMap
orHashSet
scala.collection.concurrent
- Mutable, concurrent data-structures such asTrieMap
scala.collection.parallel.immutable
- Immutable, parallel data-structures such asParVector
,ParRange
,ParHashMap
orParHashSet
scala.collection.parallel.mutable
- Mutable, parallel data-structures such asParArray
,ParHashMap
,ParTrieMap
orParHashSet
scala.concurrent
- Primitives for concurrent programming such asFutures
andPromises
scala.io
- Input and output operationsscala.math
- Basic math functions and additional numeric types likeBigInt
andBigDecimal
scala.sys
- Interaction with other processes and the operating systemscala.util.matching
- Regular expressionsOther packages exist. See the complete list on the right.
Additional parts of the standard library are shipped as separate libraries. These include:
scala.reflect
- Scala's reflection API (scala-reflect.jar)scala.xml
- XML parsing, manipulation, and serialization (scala-xml.jar)scala.swing
- A convenient wrapper around Java's GUI framework called Swing (scala-swing.jar)scala.util.parsing
- Parser combinators, including an example implementation of a JSON parser (scala-parser-combinators.jar)Automatic imports
Identifiers in the scala package and the
scala.Predef
object are always in scope by default.Some of these identifiers are type aliases provided as shortcuts to commonly used classes. For example,
List
is an alias forscala.collection.immutable.List
.Other aliases refer to classes provided by the underlying platform. For example, on the JVM,
String
is an alias forjava.lang.String
.