本文整理汇总了Scala中language.experimental.macros类的典型用法代码示例。如果您正苦于以下问题:Scala macros类的具体用法?Scala macros怎么用?Scala macros使用的例子?那么恭喜您, 这里精选的类代码示例或许可以为您提供帮助。
在下文中一共展示了macros类的5个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于我们的系统推荐出更棒的Scala代码示例。
示例1: DSLFeature
//设置package包名称以及导入依赖的类
package org.scala_lang.virtualized
import scala.reflect.macros.blackbox.Context
import language.experimental.macros
import scala.util.matching.Regex
trait MacroModule {
type Ctx <: Context
val c: Ctx
}
trait DataDefs extends MacroModule {
import c.universe._
case class DSLFeature(tpe: Option[Type], name: String, targs: List[Tree], args: List[List[Type]])
}
def className: String = ???
lazy val typeRegex = new Regex("(" + className.replace("$", "\\$") + """\.this\.)(\w*)""")
lazy val typetagRegex = new Regex("""(scala\.reflect\.runtime\.[a-zA-Z`]*\.universe\.typeTag\[)(\w*)\]""")
def code(tree: Tree, shortenDSLNames: Boolean = true): String = {
var short = showCode(tree)
if (shortenDSLNames) {
typeRegex findAllIn short foreach { m =>
val typeRegex(start, typ) = m
short = short.replace(start + typ, typ.toUpperCase())
}
typetagRegex findAllIn short foreach { m =>
val typetagRegex(start, typ) = m
short = short.replace(start + typ + "]", "TYPETAG[" + typ.toUpperCase() + "]")
}
}
short
}
}
开发者ID:GeorgOfenbeck,项目名称:websiteSpiralS,代码行数:36,代码来源:Utils.scala
示例2: Virtualizer
//设置package包名称以及导入依赖的类
package org.scala_lang.virtualized
import language.experimental.macros
import scala.annotation.StaticAnnotation
import scala.reflect.macros.blackbox.Context
val expandees = annottee match {
case Some(a) => transformer.virtualize(a)._1 :: rest
case None => rest
}
c.Expr(Block(expandees, Literal(Constant(()))))
}
private final class Virtualizer[C <: Context](val c: C)
extends LanguageVirtualization {
type Ctx = C
val debugLevel = 0
}
}
开发者ID:GeorgOfenbeck,项目名称:websiteSpiralS,代码行数:22,代码来源:Virtualize.scala
示例3: SealedTraitValues
//设置package包名称以及导入依赖的类
package com.github.nrf110.util
import language.experimental.macros
import scala.reflect.macros.blackbox
object SealedTraitValues {
def values[A]: Set[A] = macro values_impl[A]
def values_impl[A: c.WeakTypeTag](c: blackbox.Context) = {
import c.universe._
val symbol = weakTypeOf[A].typeSymbol
def isSubtype(candidate: Symbol): Boolean = {
candidate == symbol || candidate.typeSignature.baseClasses.drop(1).exists(isSubtype)
}
if (!symbol.isClass) c.abort(
c.enclosingPosition,
"Can only enumerate values of a sealed trait or class."
) else if (!symbol.asClass.isSealed) c.abort(
c.enclosingPosition,
"Can only enumerate values of a sealed trait or class."
) else {
// check all sibling declarations for subtypes
val siblingSubclasses: List[Symbol] = scala.util.Try {
c.internal.enclosingOwner.owner.typeSignature.decls
.filter(a => a.isClass || a.isModule || a.isModuleClass)
.filter(isSubtype).toList
} getOrElse Nil
// create a list of all known subtypes
val subclasses = symbol.asClass.knownDirectSubclasses.toList ::: siblingSubclasses
// filter traits and abstract classes out of the candidates list
val candidates = subclasses.filterNot(a => a.isClass && (a.asClass.isTrait || a.asClass.isAbstract))
if (!candidates.forall(x => x.isModuleClass || x.isModule)) c.abort(
c.enclosingPosition,
"All children must be objects."
) else c.Expr[Set[A]] {
def sourceModuleRef(sym: Symbol) = Ident(
if (sym.isModule) sym else
sym.asInstanceOf[
scala.reflect.internal.Symbols#Symbol
].sourceModule.asInstanceOf[Symbol]
)
Apply(
Select(
reify(Set).tree,
TermName("apply")
),
candidates.map(sourceModuleRef(_))
)
}
}
}
}
开发者ID:nrf110,项目名称:scala-common,代码行数:61,代码来源:SealedTraitValues.scala
示例4: LoadFile
//设置package包名称以及导入依赖的类
package loadFile
import java.io.{BufferedInputStream, FileInputStream}
import java.nio.file.{Files, Paths}
import language.experimental.macros
import scala.reflect.macros.blackbox.Context
import scala.io.Source
import org.apache.commons.codec.binary.Base64
import org.apache.commons.io.IOUtils
object LoadFile {
def syncLoad(fileName: String): String = macro syncLoadImpl
def syncLoadImpl(c: Context)(fileName: c.Expr[String]): c.Expr[String] = {
import c.universe._
val Literal(Constant(fileNameStr)) = fileName.tree
val fileContents = Source.fromFile("./server/public/" + fileNameStr).getLines.mkString("\n")
c.Expr[String](Literal(Constant(fileContents)))
}
def toBase64(fileName: String): String = macro toBase64Impl
def toBase64Impl(c: Context)(fileName: c.Expr[String]): c.Expr[String] = {
import c.universe._
val Literal(Constant(fileNameStr)) = fileName.tree
return c.Expr[String](Literal(Constant(new String(""))))
//val bis = new BufferedInputStream(new FileInputStream("./server/public/" + fileNameStr))
// Get byte array for base64 encoding
//val fileBytes = Stream.continually(bis.read).takeWhile(-1 != _).map(_.toByte).toArray
//val fileBytes = IOUtils.toByteArray(bis)
val fileBytes = Files.readAllBytes(Paths.get("./server/public/" + fileNameStr))
c.Expr[String](Literal(Constant(new String(Base64.encodeBase64(fileBytes)))))
}
}
开发者ID:gvatn,项目名称:play-scalajs-webgl-spark,代码行数:36,代码来源:LoadFile.scala
示例5: Port
//设置package包名称以及导入依赖的类
package msc
import scalaz.\/
import scalaz.syntax.either._
import language.experimental.macros
import scala.reflect.macros.blackbox
final class Port private(val value: Int) extends AnyVal
object Port {
def parse(p: Int): String \/ Port =
if (1024 <= p && p < 65536) new Port(p).right
else s"$p is out of range".left
def apply(i: Int): Port = macro impl
def impl(c: blackbox.Context)(i: c.Tree) = {
import c.universe._
def fail(s: String) = {
val pos = c.enclosingPosition
c.abort(pos.withPoint(pos.point + 1), s)
}
i match {
case Literal(Constant(p: Int)) =>
Port.parse(p) valueOr fail
q"""
_root_.msc.Port.parse($p) valueOr _root_.scala.sys.error
"""
case other =>
fail(other + " is not an Int literal. Use Port.parse instead.")
}
}
}
开发者ID:mjhopkins,项目名称:macro-smart-constructors,代码行数:38,代码来源:Port.scala
注:本文中的language.experimental.macros类示例整理自Github/MSDocs等源码及文档管理平台,相关代码片段筛选自各路编程大神贡献的开源项目,源码版权归原作者所有,传播和使用请参考对应项目的License;未经允许,请勿转载。 |
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