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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 12:02:58 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 12:02:58 +0000 |
commit | 698f8c2f01ea549d77d7dc3338a12e04c11057b9 (patch) | |
tree | 173a775858bd501c378080a10dca74132f05bc50 /vendor/serde_json/src/iter.rs | |
parent | Initial commit. (diff) | |
download | rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.tar.xz rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.zip |
Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | vendor/serde_json/src/iter.rs | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/vendor/serde_json/src/iter.rs b/vendor/serde_json/src/iter.rs new file mode 100644 index 000000000..9792916dc --- /dev/null +++ b/vendor/serde_json/src/iter.rs @@ -0,0 +1,70 @@ +use crate::io; + +pub struct LineColIterator<I> { + iter: I, + + /// Index of the current line. Characters in the first line of the input + /// (before the first newline character) are in line 1. + line: usize, + + /// Index of the current column. The first character in the input and any + /// characters immediately following a newline character are in column 1. + /// The column is 0 immediately after a newline character has been read. + col: usize, + + /// Byte offset of the start of the current line. This is the sum of lengths + /// of all previous lines. Keeping track of things this way allows efficient + /// computation of the current line, column, and byte offset while only + /// updating one of the counters in `next()` in the common case. + start_of_line: usize, +} + +impl<I> LineColIterator<I> +where + I: Iterator<Item = io::Result<u8>>, +{ + pub fn new(iter: I) -> LineColIterator<I> { + LineColIterator { + iter, + line: 1, + col: 0, + start_of_line: 0, + } + } + + pub fn line(&self) -> usize { + self.line + } + + pub fn col(&self) -> usize { + self.col + } + + pub fn byte_offset(&self) -> usize { + self.start_of_line + self.col + } +} + +impl<I> Iterator for LineColIterator<I> +where + I: Iterator<Item = io::Result<u8>>, +{ + type Item = io::Result<u8>; + + fn next(&mut self) -> Option<io::Result<u8>> { + match self.iter.next() { + None => None, + Some(Ok(b'\n')) => { + self.start_of_line += self.col + 1; + self.line += 1; + self.col = 0; + Some(Ok(b'\n')) + } + Some(Ok(c)) => { + self.col += 1; + Some(Ok(c)) + } + Some(Err(e)) => Some(Err(e)), + } + } +} |