Scala和其他语言的一个(在我看来是好的)区别是，它允许你用几乎任何字符来命名你的方法。

您列举的不是“标点符号”，而是简单明了的方法，因此它们的行为因对象而异(尽管存在一些约定)。

例如，查看Scaladoc文档中的List，您将看到这里提到的一些方法。

请记住以下几点:

大多数情况下，A操作符+= B组合转换为A = A操作符B，如||=或++=示例。 以:结尾的方法是右结合的，这意味着A:: B实际上是B.::(A)。

您可以通过浏览Scala文档找到大部分答案。在这里保留一个参考将重复工作，并且它将很快落后:)

你可以先根据某些标准对它们进行分组。在这篇文章中，我将只解释下划线字符和右箭头。

_._ contains a period. A period in Scala always indicates a method call. So left of the period you have the receiver, and right of it the message (method name). Now _ is a special symbol in Scala. There are several posts about it, for example this blog entry all use cases. Here it is an anonymous function short cut, that is it a shortcut for a function that takes one argument and invokes the method _ on it. Now _ is not a valid method, so most certainly you were seeing _._1 or something similar, that is, invoking method _._1 on the function argument. _1 to _22 are the methods of tuples which extract a particular element of a tuple. Example:

val tup = ("Hallo", 33)
tup._1 // extracts "Hallo"
tup._2 // extracts 33

现在让我们假设函数应用程序快捷方式的用例。给定一个将整数映射到字符串的映射:

val coll = Map(1 -> "Eins", 2 -> "Zwei", 3 -> "Drei")

Wooop, there is already another occurrence of a strange punctuation. The hyphen and greater-than characters, which resemble a right-hand arrow, is an operator which produces a Tuple2. So there is no difference in the outcome of writing either (1, "Eins") or 1 -> "Eins", only that the latter is easier to read, especially in a list of tuples like the map example. The -> is no magic, it is, like a few other operators, available because you have all implicit conversions in object scala.Predef in scope. The conversion which takes place here is

implicit def any2ArrowAssoc [A] (x: A): ArrowAssoc[A] 

其中ArrowAssoc有->方法，用于创建Tuple2。因此，1 ->“Eins”实际上是调用Predef.any2ArrowAssoc(1).->(“Eins”)。好的。现在回到带有下划线字符的原始问题:

// lets create a sequence from the map by returning the
// values in reverse.
coll.map(_._2.reverse) // yields List(sniE, iewZ, ierD)

这里的下划线缩短了以下等效代码:

coll.map(tup => tup._2.reverse)

注意map的map方法将key和value的元组传递给函数参数。由于我们只对值(字符串)感兴趣，所以我们使用元组上的_2方法提取它们。

Regarding :: there is another Stackoverflow entry which covers the :: case. In short, it is used to construct Lists by 'consing' a head element and a tail list. It is both a class which represents a cons'ed list and which can be used as an extractor, but most commonly it is a method on a list. As Pablo Fernandez points out, since it ends in a colon, it is right associative, meaning the receiver of the method call is to the right, and the argument to the left of the operator. That way you can elegantly express the consing as prepending a new head element to an existing list:

val x = 2 :: 3 :: Nil  // same result as List(2, 3)
val y = 1 :: x         // yields List(1, 2, 3)

这相当于

val x = Nil.::(3).::(2) // successively prepend 3 and 2 to an empty list
val y = x.::(1)         // then prepend 1

作为提取器对象的用法如下:

def extract(l: List[Int]) = l match {
   case Nil          => "empty"
   case head :: Nil  => "exactly one element (" + head + ")"
   case head :: tail => "more than one element"
}

extract(Nil)          // yields "empty"
extract(List(1))      // yields "exactly one element (1)"
extract(List(2, 3))   // yields "more than one element"

这看起来像一个运算符，但它实际上只是另一种(更可读的)书写方式

def extract2(l: List[Int]) = l match {
   case Nil            => "empty"
   case ::(head, Nil)  => "exactly one element (" + head + ")"
   case ::(head, tail) => "more than one element"
}

你可以在这篇文章中阅读更多关于提取器的信息。

<=就像你会“读”它:'小于或等于'。所以它是一个数学运算符，在<(小于?)、>(大于?)、==(等于?)、!=(不等于?)、<=(小于或等于?)和>=(大于或等于?)的列表中。

这不能与=>混淆，后者是一种右向双箭头，用于将参数列表与函数体分离，并将模式匹配中的测试条件(case块)与匹配发生时执行的函数体分离。你可以在我之前的两个回答中看到这样的例子。一、函数使用:

coll.map(tup => tup._2.reverse)

它已经被缩写为省略了类型。接下来的函数是

// function arguments         function body
(tup: Tuple2[Int, String]) => tup._2.reverse

与模式匹配使用:

def extract2(l: List[Int]) = l match {
   // if l matches Nil    return "empty"
   case Nil            => "empty"
   // etc.
   case ::(head, Nil)  => "exactly one element (" + head + ")"
   // etc.
   case ::(head, tail) => "more than one element"
}

Scala继承了Java的大部分算术运算符。这包括位-或|(单个管道字符)、位-和&、位-异-或^，以及逻辑(boolean)或||(两个管道字符)和逻辑-和&&。有趣的是，你可以在布尔上使用单字符操作符，所以java的逻辑操作符是完全多余的:

true && true   // valid
true & true    // valid as well

3 & 4          // bitwise-and (011 & 100 yields 000)
3 && 4         // not valid

正如在另一篇文章中指出的那样，以等号=结尾的调用将通过重赋来解析(如果该名称不存在!):

var x = 3
x += 1         // `+=` is not a method in `int`, Scala makes it `x = x + 1`

这种“双重检查”使得可以轻松地将可变集合转换为不可变集合:

val m = collection.mutable.Set("Hallo")   // `m` a val, but holds mutable coll
var i = collection.immutable.Set("Hallo") // `i` is a var, but holds immutable coll

m += "Welt" // destructive call m.+=("Welt")
i += "Welt" // re-assignment i = i + "Welt" (creates a new immutable Set)

为了便于教学，我将运算符分为四类:

关键字/保留符号 自动导入的方法 常用的方法 语法糖/成分

幸运的是，大多数类别都体现在这个问题中:

->    // Automatically imported method
||=   // Syntactic sugar
++=   // Syntactic sugar/composition or common method
<=    // Common method
_._   // Typo, though it's probably based on Keyword/composition
::    // Common method
:+=   // Common method

大多数这些方法的确切含义取决于定义它们的类。例如，<=在Int上表示“小于或等于”。第一个，->，我将在下面给出一个例子。::可能是定义在List上的方法(尽管它可以是同名的对象)，而:+=可能是定义在各种Buffer类上的方法。

我们来看看。

关键字/保留符号

Scala中有一些特殊的符号。其中两个被认为是合适的关键字，而其他的只是“保留”。它们是:

// Keywords
<-  // Used on for-comprehensions, to separate pattern from generator
=>  // Used for function types, function literals and import renaming

// Reserved
( )        // Delimit expressions and parameters
[ ]        // Delimit type parameters
{ }        // Delimit blocks
.          // Method call and path separator
// /* */   // Comments
#          // Used in type notations
:          // Type ascription or context bounds
<: >: <%   // Upper, lower and view bounds
<? <!      // Start token for various XML elements
" """      // Strings
'          // Indicate symbols and characters
@          // Annotations and variable binding on pattern matching
`          // Denote constant or enable arbitrary identifiers
,          // Parameter separator
;          // Statement separator
_*         // vararg expansion
_          // Many different meanings

这些都是该语言的一部分，因此，可以在任何正确描述该语言的文本中找到，例如Scala规范(PDF)本身。

最后一个，下划线，值得特别描述，因为它被广泛使用，有很多不同的含义。下面是一个例子:

import scala._    // Wild card -- all of Scala is imported
import scala.{ Predef => _, _ } // Exception, everything except Predef
def f[M[_]]       // Higher kinded type parameter
def f(m: M[_])    // Existential type
_ + _             // Anonymous function placeholder parameter
m _               // Eta expansion of method into method value
m(_)              // Partial function application
_ => 5            // Discarded parameter
case _ =>         // Wild card pattern -- matches anything
f(xs: _*)         // Sequence xs is passed as multiple parameters to f(ys: T*)
case Seq(xs @ _*) // Identifier xs is bound to the whole matched sequence

不过我可能忘了别的意思。

自动导入的方法

因此，如果您在上面的列表中没有找到要查找的符号，那么它一定是一个方法，或者是一个方法的一部分。但是，通常情况下，你会看到一些符号和类的文档没有那个方法。当发生这种情况时，要么您正在查看一个或多个方法与其他方法的组合，要么该方法已导入到作用域，要么通过导入的隐式转换可用。

这些仍然可以在ScalaDoc上找到:您只需要知道在哪里可以找到它们。或者，如果做不到这一点，可以看看指数(目前已突破2.9.1，但每晚都有)。

每段Scala代码都有三个自动导入:

// Not necessarily in this order
import _root_.java.lang._      // _root_ denotes an absolute path
import _root_.scala._
import _root_.scala.Predef._

前两个只使类和单例对象可用。第三个包含所有隐式转换和导入方法，因为Predef本身就是一个对象。

快速查看Predef内部显示一些符号:

class <:<
class =:=
object <%<
object =:=

任何其他符号都将通过隐式转换可用。看看带有implicit标签的方法，它们作为参数接收接收方法的类型对象。例如:

"a" -> 1  // Look for an implicit from String, AnyRef, Any or type parameter

在上面的例子中，->是在ArrowAssoc类中通过方法any2ArrowAssoc定义的，该方法接受类型为A的对象，其中A是同一方法的无界类型参数。

常用的方法

因此，许多符号只是类上的方法。例如，如果你有

List(1, 2) ++ List(3, 4)

你会在ScalaDoc for List中找到方法++。但是，在搜索方法时必须注意一个约定。以冒号(:)结尾的方法绑定到右边而不是左边。换句话说，上面的方法调用相当于:

List(1, 2).++(List(3, 4))

如果我用1::List(2,3)代替，这将等价于:

List(2, 3).::(1)

因此，在寻找以冒号结尾的方法时，需要查看右边找到的类型。举个例子:

1 +: List(2, 3) :+ 4

第一个方法(+:)绑定到右边，在List中找到。第二个方法(:+)只是一个普通的方法，并且绑定到左侧——同样是在List上。

语法糖/成分

这里有一些可能隐藏方法的语法糖:

class Example(arr: Array[Int] = Array.fill(5)(0)) {
  def apply(n: Int) = arr(n)
  def update(n: Int, v: Int) = arr(n) = v
  def a = arr(0); def a_=(v: Int) = arr(0) = v
  def b = arr(1); def b_=(v: Int) = arr(1) = v
  def c = arr(2); def c_=(v: Int) = arr(2) = v
  def d = arr(3); def d_=(v: Int) = arr(3) = v
  def e = arr(4); def e_=(v: Int) = arr(4) = v
  def +(v: Int) = new Example(arr map (_ + v))
  def unapply(n: Int) = if (arr.indices contains n) Some(arr(n)) else None
}

val Ex = new Example // or var for the last example
println(Ex(0))  // calls apply(0)
Ex(0) = 2       // calls update(0, 2)
Ex.b = 3        // calls b_=(3)
// This requires Ex to be a "val"
val Ex(c) = 2   // calls unapply(2) and assigns result to c
// This requires Ex to be a "var"
Ex += 1         // substituted for Ex = Ex + 1

最后一个方法很有趣，因为任何符号方法都可以组合成类似赋值的方法。

当然，在代码中可以出现各种组合:

(_+_) // An expression, or parameter, that is an anonymous function with
      // two parameters, used exactly where the underscores appear, and
      // which calls the "+" method on the first parameter passing the
      // second parameter as argument.

作为Daniel和0__精彩回答的补充，我不得不说Scala理解某些符号的Unicode类比，所以代替

for (n <- 1 to 10) n % 2 match {
  case 0 => println("even")
  case 1 => println("odd")
}

你可以这样写

for (n ← 1 to 10) n % 2 match {
  case 0 ⇒ println("even")
  case 1 ⇒ println("odd")
}

我认为现代IDE对于理解大型scala项目至关重要。由于这些操作符也是方法，在intellij思想中，我只是控制-单击或控制-b进入定义。

你可以右键点击一个cons操作符(::)，然后在scala javadoc中说“在这个列表的开头添加一个元素”。在用户定义的操作符中，这一点变得更加关键，因为它们可能被定义为很难找到的隐式…你的IDE知道隐式的定义在哪里。

只是为其他精彩的答案锦上添花。Scala提供了两个经常被批评的符号操作符，/:(foldLeft)和:\ (foldRight)操作符，第一个是右关联操作符。所以下面三个语句是等价的:

( 1 to 100 ).foldLeft( 0, _+_ )
( 1 to 100 )./:( 0 )( _+_ )
( 0 /: ( 1 to 100 ) )( _+_ )

就像下面这三个:

( 1 to 100 ).foldRight( 0, _+_ )
( 1 to 100 ).:\( 0 )( _+_ )
( ( 1 to 100 ) :\ 0 )( _+_ )

所以你想要一个详尽的答案?这里有一个有趣的，希望完整的，相当长的列表给你:)

http://jim-mcbeath.blogspot.com/2008/12/scala-operator-cheat-sheet.html

(免责声明-这篇文章写于2008年，所以可能有点过时)

!! AbstractActor
!! Actor // Sends msg to this actor and immediately ...
!! Proxy
! Actor // Sends msg to this actor (asynchronous).
! Channel // Sends a message to this Channel.
! OutputChannel // Sends msg to this ...
! Proxy // Sends msg to this ...
!= Any // o != arg0 is the same as !(o == (arg0)).
!= AnyRef
!= Boolean
!= Byte
!= Char
!= Double
!= Float
!= Int
!= Long
!= Short
!? AbstractActor
!? Actor // Sends msg to this actor and awaits reply ...
!? Channel // Sends a message to this Channel and ...
!? Proxy
% BigInt // Remainder of BigInts
% Byte
% Char
% Double
% Float
% Int
% Long
% Short
% Elem // Returns a new element with updated attributes, resolving namespace uris from this element's scope. ...
&&& Parsers.Parser
&& Boolean
&+ NodeBuffer // Append given object to this buffer, returns reference on this NodeBuffer ...
& BigInt // Bitwise and of BigInts
& Boolean
& Byte
& Char
& Enumeration.Set32 // Equivalent to * for bit sets. ...
& Enumeration.Set64 // Equivalent to * for bit sets. ...
& Enumeration.SetXX // Equivalent to * for bit sets. ...
& Int
& Long
& Short
&~ BigInt // Bitwise and-not of BigInts. Returns a BigInt whose value is (this & ~that).
&~ Enumeration.Set32 // Equivalent to - for bit sets. ...
&~ Enumeration.Set64 // Equivalent to - for bit sets. ...
&~ Enumeration.SetXX // Equivalent to - for bit sets. ...
>>> Byte
>>> Char
>>> Int
>>> Long
>>> Short
>> BigInt // (Signed) rightshift of BigInt
>> Byte
>> Char
>> Int
>> Long
>> Short
>> Parsers.Parser // Returns into(fq)
>> Parsers.Parser // Returns into(fq)
> BigDecimal // Greater-than comparison of BigDecimals
> BigInt // Greater-than comparison of BigInts
> Byte
> Char
> Double
> Float
> Int
> Long
> Ordered
> PartiallyOrdered
> Short
>= BigDecimal // Greater-than-or-equals comparison of BigDecimals
>= BigInt // Greater-than-or-equals comparison of BigInts
>= Byte
>= Char
>= Double
>= Float
>= Int
>= Long
>= Ordered
>= PartiallyOrdered
>= Short
<< BigInt // Leftshift of BigInt
<< Byte
<< Char
<< Int
<< Long
<< Short
<< Buffer // Send a message to this scriptable object.
<< BufferProxy // Send a message to this scriptable object.
<< Map // Send a message to this scriptable object.
<< MapProxy // Send a message to this scriptable object.
<< Scriptable // Send a message to this scriptable object.
<< Set // Send a message to this scriptable object.
<< SetProxy // Send a message to this scriptable object.
<< SynchronizedBuffer // Send a message to this scriptable object.
<< SynchronizedMap // Send a message to this scriptable object.
<< SynchronizedSet // Send a message to this scriptable object.
< BigDecimal // Less-than of BigDecimals
< BigInt // Less-than of BigInts
< Byte
< Char
< Double
< Float
< Int
< Long
< Ordered
< PartiallyOrdered
< Short
< OffsetPosition // Compare this position to another, by first comparing their line numbers, ...
< Position // Compare this position to another, by first comparing their line numbers, ...
<= BigDecimal // Less-than-or-equals comparison of BigDecimals
<= BigInt // Less-than-or-equals comparison of BigInts
<= Byte
<= Char
<= Double
<= Float
<= Int
<= Long
<= Ordered
<= PartiallyOrdered
<= Short
<~ Parsers.Parser // A parser combinator for sequential composition which keeps only the left result
** Enumeration.SetXX
** Set // Intersect. It computes an intersection with set that. ...
** Set // This method is an alias for intersect. ...
* BigDecimal // Multiplication of BigDecimals
* BigInt // Multiplication of BigInts
* Byte
* Char
* Double
* Float
* Int
* Long
* Short
* Set
* RichString // return n times the current string
* Parsers.Parser // Returns a parser that repeatedly parses what this parser parses, interleaved with the `sep' parser. ...
* Parsers.Parser // Returns a parser that repeatedly parses what this parser parses
* Parsers.Parser // Returns a parser that repeatedly parses what this parser parses, interleaved with the `sep' parser. ...
* Parsers.Parser // Returns a parser that repeatedly parses what this parser parses, interleaved with the `sep' parser.
* Parsers.Parser // Returns a parser that repeatedly parses what this parser parses
++: ArrayBuffer // Prepends a number of elements provided by an iterable object ...
++: Buffer // Prepends a number of elements provided by an iterable object ...
++: BufferProxy // Prepends a number of elements provided by an iterable object ...
++: SynchronizedBuffer // Prepends a number of elements provided by an iterable object ...
++ Array // Returns an array consisting of all elements of this array followed ...
++ Enumeration.SetXX
++ Iterable // Appends two iterable objects.
++ IterableProxy // Appends two iterable objects.
++ Iterator // Returns a new iterator that first yields the elements of this ...
++ List // Appends two list objects.
++ RandomAccessSeq // Appends two iterable objects.
++ RandomAccessSeqProxy // Appends two iterable objects.
++ Seq // Appends two iterable objects.
++ SeqProxy // Appends two iterable objects.
++ IntMap // Add a sequence of key/value pairs to this map.
++ LongMap // Add a sequence of key/value pairs to this map.
++ Map // Add a sequence of key/value pairs to this map.
++ Set // Add all the elements provided by an iterator ...
++ Set // Add all the elements provided by an iterator to the set.
++ SortedMap // Add a sequence of key/value pairs to this map.
++ SortedSet // Add all the elements provided by an iterator ...
++ Stack // Push all elements provided by the given iterable object onto ...
++ Stack // Push all elements provided by the given iterator object onto ...
++ TreeHashMap
++ TreeHashMap // Add a sequence of key/value pairs to this map.
++ Collection // Operator shortcut for addAll.
++ Set // Operator shortcut for addAll.
++ ArrayBuffer // Appends two iterable objects.
++ Buffer // Appends a number of elements provided by an iterable object ...
++ Buffer // Appends a number of elements provided by an iterator ...
++ Buffer // Appends two iterable objects.
++ BufferProxy // Appends a number of elements provided by an iterable object ...
++ Map // Add a sequence of key/value pairs to this map.
++ MapProxy // Add a sequence of key/value pairs to this map.
++ PriorityQueue
++ Set // Add all the elements provided by an iterator ...
++ SynchronizedBuffer // Appends a number of elements provided by an iterable object ...
++ RichString // Appends two iterable objects.
++ RichStringBuilder // Appends a number of elements provided by an iterable object ...
++ RichStringBuilder // Appends two iterable objects.
++= Map // Add a sequence of key/value pairs to this map.
++= MapWrapper // Add a sequence of key/value pairs to this map.
++= ArrayBuffer // Appends a number of elements in an array
++= ArrayBuffer // Appends a number of elements provided by an iterable object ...
++= ArrayStack // Pushes all the provided elements onto the stack.
++= Buffer // Appends a number of elements in an array
++= Buffer // Appends a number of elements provided by an iterable object ...
++= Buffer // Appends a number of elements provided by an iterator
++= BufferProxy // Appends a number of elements provided by an iterable object ...
++= Map // Add a sequence of key/value pairs to this map.
++= MapProxy // Add a sequence of key/value pairs to this map.
++= PriorityQueue // Adds all elements provided by an Iterable object ...
++= PriorityQueue // Adds all elements provided by an iterator into the priority queue.
++= PriorityQueueProxy // Adds all elements provided by an Iterable object ...
++= PriorityQueueProxy // Adds all elements provided by an iterator into the priority queue.
++= Queue // Adds all elements provided by an Iterable object ...
++= Queue // Adds all elements provided by an iterator ...
++= QueueProxy // Adds all elements provided by an Iterable object ...
++= QueueProxy // Adds all elements provided by an iterator ...
++= Set // Add all the elements provided by an iterator ...
++= SetProxy // Add all the elements provided by an iterator ...
++= Stack // Pushes all elements provided by an Iterable object ...
++= Stack // Pushes all elements provided by an iterator ...
++= StackProxy // Pushes all elements provided by an Iterable object ...
++= StackProxy // Pushes all elements provided by an iterator ...
++= SynchronizedBuffer // Appends a number of elements provided by an iterable object ...
++= SynchronizedMap // Add a sequence of key/value pairs to this map.
++= SynchronizedPriorityQueue // Adds all elements provided by an Iterable object ...
++= SynchronizedPriorityQueue // Adds all elements provided by an iterator into the priority queue.
++= SynchronizedQueue // Adds all elements provided by an Iterable object ...
++= SynchronizedQueue // Adds all elements provided by an iterator ...
++= SynchronizedSet // Add all the elements provided by an iterator ...
++= SynchronizedStack // Pushes all elements provided by an Iterable object ...
++= SynchronizedStack // Pushes all elements provided by an iterator ...
++= RichStringBuilder // Appends a number of elements provided by an iterable object ...
+: ArrayBuffer // Prepends a single element to this buffer and return ...
+: Buffer // Prepend a single element to this buffer and return ...
+: BufferProxy // Prepend a single element to this buffer and return ...
+: ListBuffer // Prepends a single element to this buffer. It takes constant ...
+: ObservableBuffer // Prepend a single element to this buffer and return ...
+: SynchronizedBuffer // Prepend a single element to this buffer and return ...
+: RichStringBuilder // Prepend a single element to this buffer and return ...
+: BufferWrapper // Prepend a single element to this buffer and return ...
+: RefBuffer // Prepend a single element to this buffer and return ...
+ BigDecimal // Addition of BigDecimals
+ BigInt // Addition of BigInts
+ Byte
+ Char
+ Double
+ Enumeration.SetXX // Create a new set with an additional element.
+ Float
+ Int
+ List
+ Long
+ Short
+ EmptySet // Create a new set with an additional element.
+ HashSet // Create a new set with an additional element.
+ ListSet.Node // This method creates a new set with an additional element.
+ ListSet // This method creates a new set with an additional element.
+ Map
+ Map // Add a key/value pair to this map.
+ Map // Add two or more key/value pairs to this map.
+ Queue // Creates a new queue with element added at the end ...
+ Queue // Returns a new queue with all all elements provided by ...
+ Set // Add two or more elements to this set.
+ Set // Create a new set with an additional element.
+ Set1 // Create a new set with an additional element.
+ Set2 // Create a new set with an additional element.
+ Set3 // Create a new set with an additional element.
+ Set4 // Create a new set with an additional element.
+ SortedMap // Add a key/value pair to this map.
+ SortedMap // Add two or more key/value pairs to this map.
+ SortedSet // Create a new set with an additional element.
+ Stack // Push all elements provided by the given iterable object onto ...
+ Stack // Push an element on the stack.
+ TreeSet // A new TreeSet with the entry added is returned,
+ Buffer // adds "a" from the collection. Useful for chaining.
+ Collection // adds "a" from the collection. Useful for chaining.
+ Map // Add a key/value pair to this map.
+ Set // adds "a" from the collection. Useful for chaining.
+ Buffer // Append a single element to this buffer and return ...
+ BufferProxy // Append a single element to this buffer and return ...
+ Map // Add a key/value pair to this map.
+ Map // Add two or more key/value pairs to this map.
+ MapProxy // Add a key/value pair to this map.
+ MapProxy // Add two or more key/value pairs to this map.
+ ObservableBuffer // Append a single element to this buffer and return ...
+ PriorityQueue
+ Set // Add a new element to the set.
+ Set // Add two or more elements to this set.
+ SynchronizedBuffer // Append a single element to this buffer and return ...
+ Parsers.Parser // Returns a parser that repeatedly (at least once) parses what this parser parses.
+ Parsers.Parser // Returns a parser that repeatedly (at least once) parses what this parser parses.
+= Collection // adds "a" from the collection.
+= Map // Add a key/value pair to this map.
+= ArrayBuffer // Appends a single element to this buffer and returns ...
+= ArrayStack // Alias for push.
+= BitSet // Sets i-th bit to true. ...
+= Buffer // Append a single element to this buffer.
+= BufferProxy // Append a single element to this buffer.
+= HashSet // Add a new element to the set.
+= ImmutableSetAdaptor // Add a new element to the set.
+= JavaSetAdaptor // Add a new element to the set.
+= LinkedHashSet // Add a new element to the set.
+= ListBuffer // Appends a single element to this buffer. It takes constant ...
+= Map // Add a key/value pair to this map.
+= Map // Add two or more key/value pairs to this map.
+= Map // This method defines syntactic sugar for adding or modifying ...
+= MapProxy // Add a key/value pair to this map.
+= MapProxy // Add two or more key/value pairs to this map.
+= ObservableSet // Add a new element to the set.
+= PriorityQueue // Add two or more elements to this set.
+= PriorityQueue // Inserts a single element into the priority queue.
+= PriorityQueueProxy // Inserts a single element into the priority queue.
+= Queue // Inserts a single element at the end of the queue.
+= QueueProxy // Inserts a single element at the end of the queue.
+= Set // Add a new element to the set.
+= Set // Add two or more elements to this set.
+= SetProxy // Add a new element to the set.
+= Stack // Pushes a single element on top of the stack.
+= StackProxy // Pushes a single element on top of the stack.
+= SynchronizedBuffer // Append a single element to this buffer.
+= SynchronizedMap // Add a key/value pair to this map.
+= SynchronizedMap // Add two or more key/value pairs to this map.
+= SynchronizedPriorityQueue // Inserts a single element into the priority queue.
+= SynchronizedQueue // Inserts a single element at the end of the queue.
+= SynchronizedSet // Add a new element to the set.
+= SynchronizedStack // Pushes a single element on top of the stack.
+= RichStringBuilder // Append a single element to this buffer.
+= Reactions // Add a reaction.
+= RefBuffer // Append a single element to this buffer.
+= CachedFileStorage // adds a node, setting this.dirty to true as a side effect
+= IndexedStorage // adds a node, setting this.dirty to true as a side effect
+= SetStorage // adds a node, setting this.dirty to true as a side effect
-> Map.MapTo
-> Map.MapTo
-- List // Computes the difference between this list and the given list ...
-- Map // Remove a sequence of keys from this map
-- Set // Remove all the elements provided by an iterator ...
-- SortedMap // Remove a sequence of keys from this map
-- MutableIterable // Operator shortcut for removeAll.
-- Set // Operator shortcut for removeAll.
-- Map // Remove a sequence of keys from this map
-- MapProxy // Remove a sequence of keys from this map
-- Set // Remove all the elements provided by an iterator ...
--= Map // Remove a sequence of keys from this map
--= MapProxy // Remove a sequence of keys from this map
--= Set // Remove all the elements provided by an iterator ...
--= SetProxy // Remove all the elements provided by an iterator ...
--= SynchronizedMap // Remove a sequence of keys from this map
--= SynchronizedSet // Remove all the elements provided by an iterator ...
- BigDecimal // Subtraction of BigDecimals
- BigInt // Subtraction of BigInts
- Byte
- Char
- Double
- Enumeration.SetXX // Remove a single element from a set.
- Float
- Int
- List // Computes the difference between this list and the given object ...
- Long
- Short
- EmptyMap // Remove a key from this map
- EmptySet // Remove a single element from a set.
- HashMap // Remove a key from this map
- HashSet // Remove a single element from a set.
- IntMap // Remove a key from this map
- ListMap.Node // Creates a new mapping without the given key. ...
- ListMap // This creates a new mapping without the given key. ...
- ListSet.Node // - can be used to remove a single element from ...
- ListSet // - can be used to remove a single element from ...
- LongMap // Remove a key from this map
- Map // Remove a key from this map
- Map // Remove two or more keys from this map
- Map1 // Remove a key from this map
- Map2 // Remove a key from this map
- Map3 // Remove a key from this map
- Map4 // Remove a key from this map
- Set // Remove a single element from a set.
- Set // Remove two or more elements from this set.
- Set1 // Remove a single element from a set.
- Set2 // Remove a single element from a set.
- Set3 // Remove a single element from a set.
- Set4 // Remove a single element from a set.
- SortedMap // Remove a key from this map
- SortedMap // Remove two or more keys from this map
- TreeHashMap // Remove a key from this map
- TreeMap // Remove a key from this map
- TreeSet // Remove a single element from a set.
- UnbalancedTreeMap.Node // Remove a key from this map
- UnbalancedTreeMap // Remove a key from this map
- Map // Remove a key from this map
- MutableIterable
- Set
- ListBuffer // Removes a single element from the buffer and return ...
- Map // Remove a key from this map
- Map // Remove two or more keys from this map
- MapProxy // Remove a key from this map
- MapProxy // Remove two or more keys from this map
- Set // Remove a new element from the set.
- Set // Remove two or more elements from this set.
-= Buffer // removes "a" from the collection.
-= Collection // removes "a" from the collection.
-= Map // Remove a key from this map, noop if key is not present.
-= BitSet // Clears the i-th bit.
-= Buffer // Removes a single element from this buffer, at its first occurrence. ...
-= HashMap // Remove a key from this map, noop if key is not present.
-= HashSet // Removes a single element from a set.
-= ImmutableMapAdaptor // Remove a key from this map, noop if key is not present.
-= ImmutableSetAdaptor // Removes a single element from a set.
-= JavaMapAdaptor // Remove a key from this map, noop if key is not present.
-= JavaSetAdaptor // Removes a single element from a set.
-= LinkedHashMap // Remove a key from this map, noop if key is not present.
-= LinkedHashSet // Removes a single element from a set.
-= ListBuffer // Remove a single element from this buffer. It takes linear time ...
-= Map // Remove a key from this map, noop if key is not present.
-= Map // Remove two or more keys from this map
-= MapProxy // Remove a key from this map, noop if key is not present.
-= MapProxy // Remove two or more keys from this map
-= ObservableMap // Remove a key from this map, noop if key is not present.
-= ObservableSet // Removes a single element from a set.
-= OpenHashMap // Remove a key from this map, noop if key is not present.
-= Set // Remove two or more elements from this set.
-= Set // Removes a single element from a set.
-= SetProxy // Removes a single element from a set.
-= SynchronizedMap // Remove a key from this map, noop if key is not present.
-= SynchronizedMap // Remove two or more keys from this map
-= SynchronizedSet // Removes a single element from a set.
-= Reactions // Remove the given reaction.
-= CachedFileStorage // removes a tree, setting this.dirty to true as a side effect
-= IndexedStorage // removes a tree, setting this.dirty to true as a side effect
/% BigInt // Returns a pair of two BigInts containing (this / that) and (this % that).
/: Iterable // Similar to foldLeft but can be used as ...
/: IterableProxy // Similar to foldLeft but can be used as ...
/: Iterator // Similar to foldLeft but can be used as ...
/ BigDecimal // Division of BigDecimals
/ BigInt // Division of BigInts
/ Byte
/ Char
/ Double
/ Float
/ Int
/ Long
/ Short
:/: Document
::: List
:: List
:: Document
:\ Iterable // An alias for foldRight. ...
:\ IterableProxy // An alias for foldRight. ...
:\ Iterator // An alias for foldRight. ...
== Any // o == arg0 is the same as o.equals(arg0).
== AnyRef // o == arg0 is the same as if (o eq null) arg0 eq null else o.equals(arg0).
== Boolean
== Byte
== Char
== Double
== Float
== Int
== Long
== Short
? Actor // Receives the next message from this actor's mailbox.
? Channel // Receives the next message from this Channel.
? InputChannel // Receives the next message from this Channel.
? Parsers.Parser // Returns a parser that optionally parses what this parser parses.
? Parsers.Parser // Returns a parser that optionally parses what this parser parses.
\ NodeSeq // Projection function. Similar to XPath, use this \ "foo"
\\ NodeSeq // projection function. Similar to XPath, use this \\ 'foo
^ BigInt // Bitwise exclusive-or of BigInts
^ Boolean
^ Byte
^ Char
^ Int
^ Long
^ Short
^? Parsers.Parser // A parser combinator for partial function application
^? Parsers.Parser // A parser combinator for partial function application
^^ Parsers.Parser // A parser combinator for function application
^^ Parsers.Parser // A parser combinator for function application
^^ Parsers.UnitParser // A parser combinator for function application
^^^ Parsers.Parser
| BigInt // Bitwise or of BigInts
| Boolean
| Byte
| Char
| Enumeration.Set32 // Equivalent to ++ for bit sets. Returns a set ...
| Enumeration.Set32 // Equivalent to + for bit sets. Returns a set ...
| Enumeration.Set64 // Equivalent to ++ for bit sets. Returns a set ...
| Enumeration.Set64 // Equivalent to + for bit sets. Returns a set ...
| Enumeration.SetXX // Equivalent to ++ for bit sets. Returns a set ...
| Enumeration.SetXX // Equivalent to + for bit sets. Returns a set ...
| Int
| Long
| Short
| Parsers.Parser // A parser combinator for alternative composition
| Parsers.Parser // A parser combinator for alternative composition
| Parsers.UnitParser // A parser combinator for alternative composition
|| Boolean
||| Parsers.Parser
||| Parsers.Parser // A parser combinator for alternative with longest match composition
||| Parsers.Parser // A parser combinator for alternative with longest match composition
||| Parsers.UnitParser // A parser combinator for alternative with longest match composition
~! Parsers.Parser // A parser combinator for non-back-tracking sequential composition
~! Parsers.Parser // A parser combinator for non-back-tracking sequential composition with a unit-parser
~! Parsers.Parser // A parser combinator for non-back-tracking sequential composition
~! Parsers.UnitParser // A parser combinator for non-back-tracking sequential composition with a unit-parser
~! Parsers.UnitParser // A parser combinator for non-back-tracking sequential composition
~> Parsers.Parser // A parser combinator for sequential composition which keeps only the right result
~ BigInt // Returns the bitwise complement of this BigNum
~ Parsers.OnceParser // A parser combinator for sequential composition
~ Parsers.Parser // A parser combinator for sequential composition
~ Parsers
~ Parsers.OnceParser // A parser combinator for sequential composition with a unit-parser
~ Parsers.OnceParser // A parser combinator for sequential composition
~ Parsers.Parser // A parser combinator for sequential composition with a unit-parser
~ Parsers.Parser // A parser combinator for sequential composition
~ Parsers.UnitOnceParser // A parser combinator for sequential composition with a unit-parser
~ Parsers.UnitOnceParser // A parser combinator for sequential composition
~ Parsers.UnitParser // A parser combinator for sequential composition with a unit-parser
~ Parsers.UnitParser // A parser combinator for sequential composition
unary_! Boolean
unary_+ Byte
unary_+ Char
unary_+ Double
unary_+ Float
unary_+ Int
unary_+ Long
unary_+ Short
unary_- BigDecimal // Returns a BigDecimal whose value is the negation of this BigDecimal
unary_- BigInt // Returns a BigInt whose value is the negation of this BigInt
unary_- Byte
unary_- Char
unary_- Double
unary_- Float
unary_- Int
unary_- Long
unary_- Short
unary_~ Byte
unary_~ Char
unary_~ Int
unary_~ Long
unary_~ Short

这里有很好的详尽的答案。

对我来说，关键的一点是，这有两类

op提到的符号是scala sdk中的函数名。在scala中，使用这些字符(包括unicode字符)来编写函数名是合法的。这将是一个很长的列表，试图从sdk中提到所有已经在其他答案中提到的问题

还有一些符号不是函数名，而是语言语法本身的一部分，如=>，_或操作符，如&&，||等。