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author | Adriaan Moors <adriaan.moors@epfl.ch> | 2012-07-06 14:04:27 +0200 |
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committer | Dominik Gruntz <dominik.gruntz@fhnw.ch> | 2012-07-06 14:50:57 +0200 |
commit | 623b739bde7abce5271416fbd07e91dd547fd33f (patch) | |
tree | 76e439e3a0cf4530a96953cda68b7c302f8a12f1 /src/compiler/scala/tools | |
parent | c39c7276c38f9ef66fd7054609ef33627efe5177 (diff) | |
download | scala-623b739bde7abce5271416fbd07e91dd547fd33f.tar.gz scala-623b739bde7abce5271416fbd07e91dd547fd33f.tar.bz2 scala-623b739bde7abce5271416fbd07e91dd547fd33f.zip |
macro-based string interpolation formatter
This commit provides a macro based string interpolation formatter.
The macro is implemented in MacroImplementations.scala.
In order to still be able to build a new STARR, the implementation
in StringContext.f is not yet changed. This will be replaced in
a later commit.
Diffstat (limited to 'src/compiler/scala/tools')
-rw-r--r-- | src/compiler/scala/tools/reflect/FastTrack.scala | 6 | ||||
-rw-r--r-- | src/compiler/scala/tools/reflect/MacroImplementations.scala | 148 |
2 files changed, 152 insertions, 2 deletions
diff --git a/src/compiler/scala/tools/reflect/FastTrack.scala b/src/compiler/scala/tools/reflect/FastTrack.scala index 59160f87d0..8ea66979bc 100644 --- a/src/compiler/scala/tools/reflect/FastTrack.scala +++ b/src/compiler/scala/tools/reflect/FastTrack.scala @@ -15,8 +15,9 @@ trait FastTrack { import definitions._ import language.implicitConversions - private implicit def context2taggers(c0: MacroContext) : Taggers { val c: c0.type } = new { val c: c0.type = c0 } with Taggers - private implicit def context2contextreifiers(c0: MacroContext) : ContextReifiers { val c: c0.type } = new { val c: c0.type = c0 } with ContextReifiers + private implicit def context2taggers(c0: MacroContext): Taggers { val c: c0.type } = new { val c: c0.type = c0 } with Taggers + private implicit def context2contextreifiers(c0: MacroContext): ContextReifiers { val c: c0.type } = new { val c: c0.type = c0 } with ContextReifiers + private implicit def context2macroimplementations(c0: MacroContext): MacroImplementations { val c: c0.type } = new { val c: c0.type = c0 } with MacroImplementations implicit def fastTrackEntry2MacroRuntime(entry: FastTrackEntry): MacroRuntime = args => entry.run(args) type FastTrackExpander = PartialFunction[(MacroContext, Tree), Tree] @@ -42,6 +43,7 @@ trait FastTrack { ApiUniverseReify bindTo { case (c, Apply(TypeApply(_, List(tt)), List(expr))) => c.materializeExpr(c.prefix.tree, EmptyTree, expr) } MacroContextReify bindTo { case (c, Apply(TypeApply(_, List(tt)), List(expr))) => c.materializeExprForMacroContext(c.prefix.tree, expr) } ReflectRuntimeCurrentMirror bindTo { case (c, _) => scala.reflect.runtime.Macros.currentMirror(c).tree } + StringContext_f bindTo { case (c, Apply(Select(Apply(_, parts), _), args)) => c.macro_StringInterpolation_f(parts, args) } registry } }
\ No newline at end of file diff --git a/src/compiler/scala/tools/reflect/MacroImplementations.scala b/src/compiler/scala/tools/reflect/MacroImplementations.scala new file mode 100644 index 0000000000..8e5f4d8d04 --- /dev/null +++ b/src/compiler/scala/tools/reflect/MacroImplementations.scala @@ -0,0 +1,148 @@ +package scala.tools.reflect + +import scala.reflect.makro.{ReificationError, UnexpectedReificationError} +import scala.reflect.makro.runtime.Context +import scala.collection.mutable.ListBuffer +import scala.collection.mutable.Stack + +abstract class MacroImplementations { + val c: Context + + import c.universe._ + + def macro_StringInterpolation_f(parts: List[Tree], args: List[Tree]): Tree = { + // the parts all have the same position information (as the expression is generated by the compiler) + // the args have correct position information + + // the following conditions can only be violated if invoked directly + if (parts.length != args.length + 1) { + if(parts.length == 0) + c.abort(c.prefix.tree.pos, "too few parts") + else if(args.length + 1 < parts.length) + c.abort(if(args.length==0) c.enclosingPosition else args.last.pos, + "too few arguments for interpolated string") + else + c.abort(args(parts.length-1).pos, + "too many arguments for interpolated string") + } + + val stringParts = parts map { + case Literal(Constant(s: String)) => s; + case _ => throw new IllegalArgumentException("argument parts must be a list of string literals") + } + + val pi = stringParts.iterator + val bldr = new java.lang.StringBuilder + val evals = ListBuffer[ValDef]() + val ids = ListBuffer[Ident]() + val argsStack = Stack(args : _*) + + def defval(value: Tree, tpe: Type): Unit = { + val freshName = newTermName(c.fresh("arg$")) + evals += ValDef(Modifiers(), freshName, TypeTree(tpe), value) + ids += Ident(freshName) + } + + def isFlag(ch: Char): Boolean = { + ch match { + case '-' | '#' | '+' | ' ' | '0' | ',' | '(' => true + case _ => false + } + } + + def checkType(arg: Tree, variants: Type*): Option[Type] = { + variants.find(arg.tpe <:< _).orElse( + variants.find(c.inferImplicitView(arg, arg.tpe, _) != EmptyTree).orElse( + Some(variants(0)) + ) + ) + } + + def conversionType(ch: Char, arg: Tree): Option[Type] = { + ch match { + case 'b' | 'B' => + if(arg.tpe <:< NullTpe) Some(NullTpe) else Some(BooleanTpe) + case 'h' | 'H' => + Some(AnyTpe) + case 's' | 'S' => + Some(AnyTpe) + case 'c' | 'C' => + checkType(arg, CharTpe, ByteTpe, ShortTpe, IntTpe) + case 'd' | 'o' | 'x' | 'X' => + checkType(arg, IntTpe, LongTpe, ByteTpe, ShortTpe, typeOf[BigInt], typeOf[java.math.BigInteger]) + // BigInteger can be removed as soon as an implicit conversion is defined from BigInteger to BigInt + case 'e' | 'E' | 'g' | 'G' | 'f' | 'a' | 'A' => + checkType(arg, DoubleTpe, FloatTpe, typeOf[BigDecimal]) + case 't' | 'T' => + checkType(arg, LongTpe, typeOf[java.util.Calendar], typeOf[java.util.Date]) + case _ => None + } + } + + def copyString(first: Boolean): Unit = { + val str = StringContext.treatEscapes(pi.next()) + val strLen = str.length + val strIsEmpty = strLen == 0 + var start = 0 + var idx = 0 + + if (!first) { + val arg = argsStack.pop + if (strIsEmpty || (str charAt 0) != '%') { + bldr append "%s" + defval(arg, AnyTpe) + } else { + // PRE str is not empty and str(0) == '%' + // argument index parameter is not allowed, thus parse + // [flags][width][.precision]conversion + var pos = 1 + while(pos < strLen && isFlag(str charAt pos)) pos += 1 + while(pos < strLen && Character.isDigit(str charAt pos)) pos += 1 + if(pos < strLen && str.charAt(pos) == '.') { pos += 1 + while(pos < strLen && Character.isDigit(str charAt pos)) pos += 1 + } + if(pos < strLen) { + conversionType(str charAt pos, arg) match { + case Some(tpe) => defval(arg, tpe) + case None => c.error(arg.pos, "illegal conversion character") + } + } else { + // TODO: place error message on conversion string + c.error(arg.pos, "wrong conversion string") + } + } + idx = 1 + } + if (!strIsEmpty) { + val len = str.length + while (idx < len) { + if (str(idx) == '%') { + bldr append (str substring (start, idx)) append "%%" + start = idx + 1 + } + idx += 1 + } + bldr append (str substring (start, idx)) + } + } + + copyString(first = true) + while (pi.hasNext) { + copyString(first = false) + } + + val fstring = bldr.toString +// val expr = c.reify(fstring.format((ids.map(id => Expr(id).eval)) : _*)) +// https://issues.scala-lang.org/browse/SI-5824, therefore + val expr = + Apply( + Select( + Literal(Constant(fstring)), + newTermName("format")), + List(ids: _* ) + ); + + Block(evals.toList, expr) + } + +}
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