Constructors for expressions.
Attributes
- Companion
- class
- Source
- Expr.scala
- Graph
-
- Supertypes
- Self type
-
Expr.type
Members list
Value members
Concrete methods
Creates an expression that will construct the value x.
Creates an expression that will construct the value x.
Type parameters
- T
-
the type of the value to be lifted into an expression
Value parameters
- x
-
the value to lift into a quoted expression
Attributes
- Source
- Expr.scala
e.betaReduce returns an expression that is functionally equivalent to e, however if e is of the form ((y1, ..., yn) => e2)(e1, ..., en) then it optimizes the top most call by returning the result of beta-reducing the application. Similarly, all outermost curried function applications will be beta-reduced, if possible. Otherwise returns expr.
e.betaReduce returns an expression that is functionally equivalent to e, however if e is of the form ((y1, ..., yn) => e2)(e1, ..., en) then it optimizes the top most call by returning the result of beta-reducing the application. Similarly, all outermost curried function applications will be beta-reduced, if possible. Otherwise returns expr.
To retain semantics the argument ei is bound as val yi = ei and by-name arguments to def yi = ei. Some bindings may be elided as an early optimization.
Example:
((a: Int, b: Int) => a + b).apply(x, y)
will be reduced to
val a = x
val b = y
a + b
Generally:
([X1, Y1, ...] => (x1, y1, ...) => ... => [Xn, Yn, ...] => (xn, yn, ...) => f[X1, Y1, ..., Xn, Yn, ...](x1, y1, ..., xn, yn, ...))).apply[Tx1, Ty1, ...](myX1, myY1, ...)....apply[Txn, Tyn, ...](myXn, myYn, ...)
will be reduced to
type X1 = Tx1
type Y1 = Ty1
...
val x1 = myX1
val y1 = myY1
...
type Xn = Txn
type Yn = Tyn
...
val xn = myXn
val yn = myYn
...
f[X1, Y1, ..., Xn, Yn, ...](x1, y1, ..., xn, yn, ...)
Type parameters
- T
-
the type of the expression to beta-reduce
Value parameters
- expr
-
the expression to beta-reduce
Attributes
- Returns
-
the beta-reduced expression, or
exprunchanged if no reduction is possible - Source
- Expr.scala
Returns an expression containing a block with the given statements and ending with the expression Given list of statements s1 :: s2 :: ... :: Nil and an expression e the resulting expression will be equivalent to '{ $s1; $s2; ...; $e }.
Returns an expression containing a block with the given statements and ending with the expression Given list of statements s1 :: s2 :: ... :: Nil and an expression e the resulting expression will be equivalent to '{ $s1; $s2; ...; $e }.
Type parameters
- T
-
the type of the final expression, which determines the block's result type
Value parameters
- expr
-
the final expression whose value becomes the result of the block
- statements
-
the statements to execute before the final expression in the block
Attributes
- Source
- Expr.scala
Creates an expression that will construct a copy of this list
Creates an expression that will construct a copy of this list
Transforms a list of expression List(e1, e2, ...) where ei: Expr[T] to an expression equivalent to '{ List($e1, $e2, ...) } typed as an Expr[List[T]]
Type parameters
- T
-
the element type of the list
Value parameters
- xs
-
the sequence of expressions to combine into a list expression
Attributes
- Returns
-
an expression representing a
List[T]constructed from the given element expressions - Source
- Expr.scala
Creates an expression that will construct a copy of this sequence
Creates an expression that will construct a copy of this sequence
Transforms a sequence of expression Seq(e1, e2, ...) where ei: Expr[T] to an expression equivalent to '{ Seq($e1, $e2, ...) } typed as an Expr[Seq[T]]
Type parameters
- T
-
the element type of the sequence
Value parameters
- xs
-
the sequence of expressions to combine
Attributes
- Returns
-
an expression representing a
Seq[T]constructed from the given element expressions - Source
- Expr.scala
Given a tuple of the form (Expr[A1], ..., Expr[An]), outputs a tuple Expr[(A1, ..., An)].
Given a tuple of the form (Expr[A1], ..., Expr[An]), outputs a tuple Expr[(A1, ..., An)].
Type parameters
- T
-
the tuple type where each element is wrapped in
Expr, e.g.,(Expr[A1], ..., Expr[An])
Attributes
- Source
- Expr.scala
Creates an expression that will construct a copy of this tuple
Creates an expression that will construct a copy of this tuple
Transforms a sequence of expression Seq(e1, e2, ...) where ei: Expr[Any] to an expression equivalent to '{ ($e1, $e2, ...) } typed as an Expr[Tuple]
Value parameters
- seq
-
the sequence of element expressions to combine into a tuple expression
Attributes
- Returns
-
an expression representing a tuple constructed from the given element expressions
- Source
- Expr.scala
Finds a given instance of type T in the current scope. Returns Some containing the expression of the implicit or None if implicit resolution failed.
Finds a given instance of type T in the current scope. Returns Some containing the expression of the implicit or None if implicit resolution failed.
Type parameters
- T
-
type of the implicit parameter
Attributes
- Source
- Expr.scala
Finds a given instance of type T in the current scope, while excluding certain symbols from the initial implicit search. Returns Some containing the expression of the implicit or None if implicit resolution failed.
Finds a given instance of type T in the current scope, while excluding certain symbols from the initial implicit search. Returns Some containing the expression of the implicit or None if implicit resolution failed.
Type parameters
- T
-
type of the implicit parameter
Value parameters
- ignored
-
Symbols ignored during the initial implicit search
Attributes
- Returns
-
Somecontaining the found implicit expression, orNoneif implicit resolution failed - Note
-
if the found given requires additional search for other given instances, this additional search will NOT exclude the symbols from the
ignoredlist. - Source
- Expr.scala
Gets Some of a copy of the value if the expression contains a literal constant or constructor of T. Otherwise returns None.
Gets Some of a copy of the value if the expression contains a literal constant or constructor of T. Otherwise returns None.
Usage:
case '{ ... ${expr @ Expr(value)}: T ...} =>
// expr: Expr[T]
// value: T
To directly get the value of an expression expr: Expr[T] consider using expr.value/expr.valueOrError instead.
Type parameters
- T
-
the type of the value to extract from the expression
Value parameters
- x
-
the expression to extract a value from
Attributes
- Returns
-
Somecontaining the extracted value ifxis a literal constant or known constructor,Noneotherwise - Source
- Expr.scala