aboutsummaryrefslogtreecommitdiff
path: root/vendor/serde_json/src/iter.rs
diff options
context:
space:
mode:
Diffstat (limited to 'vendor/serde_json/src/iter.rs')
-rw-r--r--vendor/serde_json/src/iter.rs70
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 0000000..9792916
--- /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)),
+ }
+ }
+}