LinesView

public struct LinesView { /* private fields */ }

A view over the lines of a String, split on \n, \r\n, or \r.

Returned by String.lines. The yielded strings (from iteration or single-line subscripting) do not include the terminator; a trailing line without a terminator is still emitted. Range subscripts (lines(0..<n)) yield a zero-copy LinesView sub-view whose underlying byte range still includes the original terminators — iterating the sub-view round-trips the same line strings, and .toString() reconstructs the original substring exactly.

Examples

var lines = Array[String]();
for line in "a\nb\nc".lines {
    lines.append(line);
}
lines.count;  // 3

// Range subscript preserves terminators in the underlying bytes:
"a\r\nb\nc".lines(0..<2).toString();  // "a\r\nb\n"

Representation

A (ptr, length) pair pointing into the source string.

Properties

public var count: Int64 { get }

Number of lines in the view. O(n) — walks the buffer scanning for terminators. Cache the result if you need it more than once.

public var endIndex: LineIndex { get }

Line index at the end (one past the last byte).

public var first: String? { get }

The first line (without terminator), or None if the view is empty.

O(first line length) — scans for the first terminator.

public var isEmpty: Bool { get }

true when the view spans zero bytes (no lines).

O(1) — checks byteCount, not count.

public var startIndex: LineIndex { get }

Line index at byte 0.

Initializers

public init(slice: StringSlice)

Constructs a lines view backed by the given string slice. The view retains shared ownership of the underlying bytes.

Methods

public func index(at: Int64) -> LineIndex?

Resolves the n-th line to its byte offset. O(n) — scans for line terminators from the start.

public func indexedIter() -> IndexedLinesIterator

Returns an iterator yielding (LineIndex, String) pairs.

public func slice(from: LineIndex, to: LineIndex) -> StringSlice

Returns a StringSlice covering [start, end) by byte offset.

public func substring[__opaque_0](__opaque_0) -> String where __opaque_0: LinesSubstringIndex

Convenience: dispatches to a LinesSubstringIndex to produce an owned String covering the requested line range, with their original terminators preserved. Equivalent to self(range).toString() for both Range[Int64] and ClosedRange[Int64].

public func toString() -> String

Materializes the view as an owned String covering the entire underlying buffer (terminators included). O(n) — copies bytes.

Subscripts

public subscript[I](checked: I) -> I.LinesYield? { get }

Reads at index, returning .None on out-of-bounds.

public subscript[I](clamped: I) -> I.LinesClampedYield { get }

Reads at index saturated to [0, count). Single-line indexes yield String? (.None only when the view holds no lines); range indexes yield LinesView (always valid, possibly empty).

public subscript[I](I) -> I.LinesYield { get }

Int64 reads a single line as a String (without terminator). Range[Int64] / ClosedRange[Int64] yield a zero-copy LinesView sub-view covering those lines (terminators preserved in the underlying bytes). O(n) — walks the buffer from the start. Panics on out-of-bounds.

public subscript[I](wrapped: I) -> I.LinesWrappedYield { get }

Reads at index with modulo wrap-around. Negative indices wrap from the end: view.lines(wrapped: -1) reads the last line. Returns None on an empty view.

ImplementsIterable

Associated Types

type Item = String

The element type yielded by iteration — always String.

type TargetIterator = LinesIterator

The iterator type returned by iter().

Methods

public func iter() -> LinesIterator

Returns a LinesIterator positioned at byte 0.

ImplementsCloneable

Methods

public func clone() -> LinesView

Defined in lang/std/text/views.ks