blob: a3d5f5f8958fe79b922f13fa5c1306f14bb98350 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
|
/* __ *\
** ________ ___ / / ___ Scala API **
** / __/ __// _ | / / / _ | (c) 2006-2011, LAMP/EPFL **
** __\ \/ /__/ __ |/ /__/ __ | http://scala-lang.org/ **
** /____/\___/_/ |_/____/_/ | | **
** |/ **
\* */
package scala.util.parsing.input
/** An object encapsulating basic character constants.
*
* @author Martin Odersky, Adriaan Moors
*/
object CharSequenceReader {
final val EofCh = '\032'
}
/** A character array reader reads a stream of characters (keeping track of their positions)
* from an array.
*
* @param source the source sequence
* @param offset starting offset.
*
* @author Martin Odersky
*/
class CharSequenceReader(override val source: java.lang.CharSequence,
override val offset: Int) extends Reader[Char] {
import CharSequenceReader._
/** Construct a `CharSequenceReader` with its first element at
* `source(0)` and position `(1,1)`.
*/
def this(source: java.lang.CharSequence) = this(source, 0)
/** Returns the first element of the reader, or EofCh if reader is at its end.
*/
def first =
if (offset < source.length) source.charAt(offset) else EofCh
/** Returns a CharSequenceReader consisting of all elements except the first.
*
* @return If `atEnd` is `true`, the result will be `this`;
* otherwise, it's a `CharSequenceReader` containing the rest of input.
*/
def rest: CharSequenceReader =
if (offset < source.length) new CharSequenceReader(source, offset + 1)
else this
/** The position of the first element in the reader.
*/
def pos: Position = new OffsetPosition(source, offset)
/** true iff there are no more elements in this reader (except for trailing
* EofCh's)
*/
def atEnd = offset >= source.length
/** Returns an abstract reader consisting of all elements except the first
* `n` elements.
*/
override def drop(n: Int): CharSequenceReader =
new CharSequenceReader(source, offset + n)
}
|
