docs: add errors example

1 files changed, 38 insertions, 0 deletions

diff --git a/examples/errors.rs b/examples/errors.rs
new file mode 100644
index 0000000..5603b9c
--- /dev/null
+++ b/examples/errors.rs
@@ -0,0 +1,38 @@
+//! Annotates errors in the HTML read from stdin.
+//! Try it out with e.g.:
+//!
+//! ```sh
+//! printf "The pirate says &arrrrr;" | cargo run --example errors
+//! ```
+
+use codespan_reporting::{
+    diagnostic::{Diagnostic, Label},
+    files::SimpleFiles,
+    term,
+    term::termcolor::{ColorChoice, StandardStream},
+};
+use html5tokenizer::{offset::PosTrackingReader, NaiveParser, TracingEmitter};
+
+fn main() {
+    let input = std::io::read_to_string(std::io::stdin()).unwrap();
+    let input_clone = input.clone();
+    let mut parser =
+        NaiveParser::new_with_emitter(PosTrackingReader::new(&input), TracingEmitter::default());
+
+    let mut files = SimpleFiles::new();
+    let file_id = files.add("stdin", input_clone);
+
+    let mut labels = Vec::new();
+
+    for _ in parser.by_ref() {}
+
+    for (error, span) in parser.emitter_mut().drain_errors() {
+        labels.push(Label::primary(file_id, span).with_message(error.code()));
+    }
+
+    let diagnostic = Diagnostic::error().with_labels(labels);
+
+    let mut writer = StandardStream::stdout(ColorChoice::Auto);
+    let config = codespan_reporting::term::Config::default();
+    term::emit(&mut writer, &config, &files, &diagnostic).unwrap();
+}