language.rs

  1mod buffer;
  2mod diagnostic_set;
  3mod highlight_map;
  4mod outline;
  5pub mod proto;
  6#[cfg(test)]
  7mod tests;
  8
  9use anyhow::{anyhow, Context, Result};
 10use client::http::HttpClient;
 11use collections::HashMap;
 12use futures::{
 13    future::{BoxFuture, Shared},
 14    FutureExt, TryFutureExt,
 15};
 16use gpui::{MutableAppContext, Task};
 17use highlight_map::HighlightMap;
 18use lazy_static::lazy_static;
 19use parking_lot::{Mutex, RwLock};
 20use regex::Regex;
 21use serde::{de, Deserialize, Deserializer};
 22use serde_json::Value;
 23use std::{
 24    any::Any,
 25    cell::RefCell,
 26    mem,
 27    ops::Range,
 28    path::{Path, PathBuf},
 29    str,
 30    sync::Arc,
 31};
 32use theme::SyntaxTheme;
 33use tree_sitter::{self, Query};
 34use util::ResultExt;
 35
 36#[cfg(any(test, feature = "test-support"))]
 37use futures::channel::mpsc;
 38
 39pub use buffer::Operation;
 40pub use buffer::*;
 41pub use diagnostic_set::DiagnosticEntry;
 42pub use outline::{Outline, OutlineItem};
 43pub use tree_sitter::{Parser, Tree};
 44
 45thread_local! {
 46    static PARSER: RefCell<Parser>  = RefCell::new(Parser::new());
 47}
 48
 49lazy_static! {
 50    pub static ref PLAIN_TEXT: Arc<Language> = Arc::new(Language::new(
 51        LanguageConfig {
 52            name: "Plain Text".into(),
 53            ..Default::default()
 54        },
 55        None,
 56    ));
 57}
 58
 59pub trait ToLspPosition {
 60    fn to_lsp_position(self) -> lsp::Position;
 61}
 62
 63#[derive(Clone, Debug, PartialEq, Eq, Hash)]
 64pub struct LanguageServerName(pub Arc<str>);
 65
 66use async_trait::async_trait;
 67
 68#[async_trait]
 69pub trait LspAdapter: 'static + Send + Sync {
 70    async fn name(&self) -> LanguageServerName;
 71    async fn fetch_latest_server_version(
 72        &self,
 73        http: Arc<dyn HttpClient>,
 74    ) -> Result<Box<dyn 'static + Send + Any>>;
 75    async fn fetch_server_binary(
 76        &self,
 77        version: Box<dyn 'static + Send + Any>,
 78        http: Arc<dyn HttpClient>,
 79        container_dir: PathBuf,
 80    ) -> Result<PathBuf>;
 81    async fn cached_server_binary(
 82        &self,
 83        container_dir: PathBuf,
 84    ) -> BoxFuture<'static, Option<PathBuf>>;
 85
 86    async fn process_diagnostics(&self, _: &mut lsp::PublishDiagnosticsParams) {}
 87
 88    async fn label_for_completion(
 89        &self,
 90        _: &lsp::CompletionItem,
 91        _: &Language,
 92    ) -> Option<CodeLabel> {
 93        None
 94    }
 95
 96    async fn label_for_symbol(
 97        &self,
 98        _: &str,
 99        _: lsp::SymbolKind,
100        _: &Language,
101    ) -> Option<CodeLabel> {
102        None
103    }
104
105    async fn server_args(&self) -> Vec<String> {
106        Vec::new()
107    }
108
109    async fn initialization_options(&self) -> Option<Value> {
110        None
111    }
112
113    async fn disk_based_diagnostic_sources(&self) -> &'static [&'static str] {
114        Default::default()
115    }
116
117    async fn disk_based_diagnostics_progress_token(&self) -> Option<&'static str> {
118        None
119    }
120
121    async fn id_for_language(&self, _name: &str) -> Option<String> {
122        None
123    }
124}
125
126#[derive(Clone, Debug, PartialEq, Eq)]
127pub struct CodeLabel {
128    pub text: String,
129    pub runs: Vec<(Range<usize>, HighlightId)>,
130    pub filter_range: Range<usize>,
131}
132
133#[derive(Deserialize)]
134pub struct LanguageConfig {
135    pub name: Arc<str>,
136    pub path_suffixes: Vec<String>,
137    pub brackets: Vec<BracketPair>,
138    #[serde(default = "auto_indent_using_last_non_empty_line_default")]
139    pub auto_indent_using_last_non_empty_line: bool,
140    #[serde(default, deserialize_with = "deserialize_regex")]
141    pub increase_indent_pattern: Option<Regex>,
142    #[serde(default, deserialize_with = "deserialize_regex")]
143    pub decrease_indent_pattern: Option<Regex>,
144    #[serde(default)]
145    pub autoclose_before: String,
146    pub line_comment: Option<String>,
147}
148
149impl Default for LanguageConfig {
150    fn default() -> Self {
151        Self {
152            name: "".into(),
153            path_suffixes: Default::default(),
154            brackets: Default::default(),
155            auto_indent_using_last_non_empty_line: auto_indent_using_last_non_empty_line_default(),
156            increase_indent_pattern: Default::default(),
157            decrease_indent_pattern: Default::default(),
158            autoclose_before: Default::default(),
159            line_comment: Default::default(),
160        }
161    }
162}
163
164fn auto_indent_using_last_non_empty_line_default() -> bool {
165    true
166}
167
168fn deserialize_regex<'de, D: Deserializer<'de>>(d: D) -> Result<Option<Regex>, D::Error> {
169    let source = Option::<String>::deserialize(d)?;
170    if let Some(source) = source {
171        Ok(Some(regex::Regex::new(&source).map_err(de::Error::custom)?))
172    } else {
173        Ok(None)
174    }
175}
176
177#[cfg(any(test, feature = "test-support"))]
178pub struct FakeLspAdapter {
179    pub name: &'static str,
180    pub capabilities: lsp::ServerCapabilities,
181    pub initializer: Option<Box<dyn 'static + Send + Sync + Fn(&mut lsp::FakeLanguageServer)>>,
182    pub disk_based_diagnostics_progress_token: Option<&'static str>,
183    pub disk_based_diagnostics_sources: &'static [&'static str],
184}
185
186#[derive(Clone, Debug, Deserialize)]
187pub struct BracketPair {
188    pub start: String,
189    pub end: String,
190    pub close: bool,
191    pub newline: bool,
192}
193
194pub struct Language {
195    pub(crate) config: LanguageConfig,
196    pub(crate) grammar: Option<Arc<Grammar>>,
197    pub(crate) adapter: Option<Arc<dyn LspAdapter>>,
198
199    #[cfg(any(test, feature = "test-support"))]
200    fake_adapter: Option<(
201        mpsc::UnboundedSender<lsp::FakeLanguageServer>,
202        Arc<FakeLspAdapter>,
203    )>,
204}
205
206pub struct Grammar {
207    pub(crate) ts_language: tree_sitter::Language,
208    pub(crate) highlights_query: Option<Query>,
209    pub(crate) brackets_query: Option<Query>,
210    pub(crate) indents_query: Option<Query>,
211    pub(crate) outline_query: Option<Query>,
212    pub(crate) highlight_map: Mutex<HighlightMap>,
213}
214
215#[derive(Clone)]
216pub enum LanguageServerBinaryStatus {
217    CheckingForUpdate,
218    Downloading,
219    Downloaded,
220    Cached,
221    Failed { error: String },
222}
223
224pub struct LanguageRegistry {
225    languages: RwLock<Vec<Arc<Language>>>,
226    language_server_download_dir: Option<Arc<Path>>,
227    lsp_binary_statuses_tx: async_broadcast::Sender<(Arc<Language>, LanguageServerBinaryStatus)>,
228    lsp_binary_statuses_rx: async_broadcast::Receiver<(Arc<Language>, LanguageServerBinaryStatus)>,
229    login_shell_env_loaded: Shared<Task<()>>,
230    lsp_binary_paths: Mutex<
231        HashMap<
232            LanguageServerName,
233            Shared<BoxFuture<'static, Result<PathBuf, Arc<anyhow::Error>>>>,
234        >,
235    >,
236}
237
238impl LanguageRegistry {
239    pub fn new(login_shell_env_loaded: Task<()>) -> Self {
240        let (lsp_binary_statuses_tx, lsp_binary_statuses_rx) = async_broadcast::broadcast(16);
241        Self {
242            language_server_download_dir: None,
243            languages: Default::default(),
244            lsp_binary_statuses_tx,
245            lsp_binary_statuses_rx,
246            login_shell_env_loaded: login_shell_env_loaded.shared(),
247            lsp_binary_paths: Default::default(),
248        }
249    }
250
251    #[cfg(any(test, feature = "test-support"))]
252    pub fn test() -> Self {
253        Self::new(Task::ready(()))
254    }
255
256    pub fn add(&self, language: Arc<Language>) {
257        self.languages.write().push(language.clone());
258    }
259
260    pub fn set_theme(&self, theme: &SyntaxTheme) {
261        for language in self.languages.read().iter() {
262            language.set_theme(theme);
263        }
264    }
265
266    pub fn set_language_server_download_dir(&mut self, path: impl Into<Arc<Path>>) {
267        self.language_server_download_dir = Some(path.into());
268    }
269
270    pub fn get_language(&self, name: &str) -> Option<Arc<Language>> {
271        self.languages
272            .read()
273            .iter()
274            .find(|language| language.name().to_lowercase() == name.to_lowercase())
275            .cloned()
276    }
277
278    pub fn to_vec(&self) -> Vec<Arc<Language>> {
279        self.languages.read().iter().cloned().collect()
280    }
281
282    pub fn language_names(&self) -> Vec<String> {
283        self.languages
284            .read()
285            .iter()
286            .map(|language| language.name().to_string())
287            .collect()
288    }
289
290    pub fn select_language(&self, path: impl AsRef<Path>) -> Option<Arc<Language>> {
291        let path = path.as_ref();
292        let filename = path.file_name().and_then(|name| name.to_str());
293        let extension = path.extension().and_then(|name| name.to_str());
294        let path_suffixes = [extension, filename];
295        self.languages
296            .read()
297            .iter()
298            .find(|language| {
299                language
300                    .config
301                    .path_suffixes
302                    .iter()
303                    .any(|suffix| dbg!(path_suffixes.contains(&Some(dbg!(suffix.as_str())))))
304            })
305            .cloned()
306    }
307
308    pub fn start_language_server(
309        self: &Arc<Self>,
310        server_id: usize,
311        language: Arc<Language>,
312        root_path: Arc<Path>,
313        http_client: Arc<dyn HttpClient>,
314        cx: &mut MutableAppContext,
315    ) -> Option<Task<Result<lsp::LanguageServer>>> {
316        #[cfg(any(test, feature = "test-support"))]
317        if language.fake_adapter.is_some() {
318            let language = language.clone();
319            return Some(cx.spawn(|cx| async move {
320                let (servers_tx, fake_adapter) = language.fake_adapter.as_ref().unwrap();
321                let (server, mut fake_server) = lsp::LanguageServer::fake(
322                    fake_adapter.name.to_string(),
323                    fake_adapter.capabilities.clone(),
324                    cx.clone(),
325                );
326
327                if let Some(initializer) = &fake_adapter.initializer {
328                    initializer(&mut fake_server);
329                }
330
331                let servers_tx = servers_tx.clone();
332                cx.background()
333                    .spawn(async move {
334                        if fake_server
335                            .try_receive_notification::<lsp::notification::Initialized>()
336                            .await
337                            .is_some()
338                        {
339                            servers_tx.unbounded_send(fake_server).ok();
340                        }
341                    })
342                    .detach();
343                Ok(server)
344            }));
345        }
346
347        let download_dir = self
348            .language_server_download_dir
349            .clone()
350            .ok_or_else(|| anyhow!("language server download directory has not been assigned"))
351            .log_err()?;
352
353        let this = self.clone();
354        let adapter = language.adapter.clone()?;
355        let lsp_binary_statuses = self.lsp_binary_statuses_tx.clone();
356        let login_shell_env_loaded = self.login_shell_env_loaded.clone();
357        Some(cx.spawn(|cx| async move {
358            login_shell_env_loaded.await;
359            let server_binary_path = this
360                .lsp_binary_paths
361                .lock()
362                .entry(adapter.name())
363                .or_insert_with(|| {
364                    get_server_binary_path(
365                        adapter.clone(),
366                        language.clone(),
367                        http_client,
368                        download_dir,
369                        lsp_binary_statuses,
370                    )
371                    .map_err(Arc::new)
372                    .boxed()
373                    .shared()
374                })
375                .clone()
376                .map_err(|e| anyhow!(e));
377
378            let server_binary_path = server_binary_path.await?;
379            let server_args = adapter.server_args();
380            let server = lsp::LanguageServer::new(
381                server_id,
382                &server_binary_path,
383                &server_args,
384                &root_path,
385                cx,
386            )?;
387            Ok(server)
388        }))
389    }
390
391    pub fn language_server_binary_statuses(
392        &self,
393    ) -> async_broadcast::Receiver<(Arc<Language>, LanguageServerBinaryStatus)> {
394        self.lsp_binary_statuses_rx.clone()
395    }
396}
397
398async fn get_server_binary_path(
399    adapter: Arc<dyn LspAdapter>,
400    language: Arc<Language>,
401    http_client: Arc<dyn HttpClient>,
402    download_dir: Arc<Path>,
403    statuses: async_broadcast::Sender<(Arc<Language>, LanguageServerBinaryStatus)>,
404) -> Result<PathBuf> {
405    let container_dir: Arc<Path> = download_dir.join(adapter.name().0.as_ref()).into();
406    if !container_dir.exists() {
407        smol::fs::create_dir_all(&container_dir)
408            .await
409            .context("failed to create container directory")?;
410    }
411
412    let path = fetch_latest_server_binary_path(
413        adapter.clone(),
414        language.clone(),
415        http_client,
416        &container_dir,
417        statuses.clone(),
418    )
419    .await;
420    if let Err(error) = path.as_ref() {
421        if let Some(cached_path) = adapter.cached_server_binary(container_dir).await {
422            statuses
423                .broadcast((language.clone(), LanguageServerBinaryStatus::Cached))
424                .await?;
425            return Ok(cached_path);
426        } else {
427            statuses
428                .broadcast((
429                    language.clone(),
430                    LanguageServerBinaryStatus::Failed {
431                        error: format!("{:?}", error),
432                    },
433                ))
434                .await?;
435        }
436    }
437    path
438}
439
440async fn fetch_latest_server_binary_path(
441    adapter: Arc<dyn LspAdapter>,
442    language: Arc<Language>,
443    http_client: Arc<dyn HttpClient>,
444    container_dir: &Path,
445    lsp_binary_statuses_tx: async_broadcast::Sender<(Arc<Language>, LanguageServerBinaryStatus)>,
446) -> Result<PathBuf> {
447    let container_dir: Arc<Path> = container_dir.into();
448    lsp_binary_statuses_tx
449        .broadcast((
450            language.clone(),
451            LanguageServerBinaryStatus::CheckingForUpdate,
452        ))
453        .await?;
454    let version_info = adapter
455        .fetch_latest_server_version(http_client.clone())
456        .await?;
457    lsp_binary_statuses_tx
458        .broadcast((language.clone(), LanguageServerBinaryStatus::Downloading))
459        .await?;
460    let path = adapter
461        .fetch_server_binary(version_info, http_client, container_dir.clone())
462        .await?;
463    lsp_binary_statuses_tx
464        .broadcast((language.clone(), LanguageServerBinaryStatus::Downloaded))
465        .await?;
466    Ok(path)
467}
468
469impl Language {
470    pub fn new(config: LanguageConfig, ts_language: Option<tree_sitter::Language>) -> Self {
471        Self {
472            config,
473            grammar: ts_language.map(|ts_language| {
474                Arc::new(Grammar {
475                    highlights_query: None,
476                    brackets_query: None,
477                    indents_query: None,
478                    outline_query: None,
479                    ts_language,
480                    highlight_map: Default::default(),
481                })
482            }),
483            adapter: None,
484
485            #[cfg(any(test, feature = "test-support"))]
486            fake_adapter: None,
487        }
488    }
489
490    pub fn lsp_adapter(&self) -> Option<Arc<dyn LspAdapter>> {
491        self.adapter.clone()
492    }
493
494    pub fn with_highlights_query(mut self, source: &str) -> Result<Self> {
495        let grammar = self.grammar_mut();
496        grammar.highlights_query = Some(Query::new(grammar.ts_language, source)?);
497        Ok(self)
498    }
499
500    pub fn with_brackets_query(mut self, source: &str) -> Result<Self> {
501        let grammar = self.grammar_mut();
502        grammar.brackets_query = Some(Query::new(grammar.ts_language, source)?);
503        Ok(self)
504    }
505
506    pub fn with_indents_query(mut self, source: &str) -> Result<Self> {
507        let grammar = self.grammar_mut();
508        grammar.indents_query = Some(Query::new(grammar.ts_language, source)?);
509        Ok(self)
510    }
511
512    pub fn with_outline_query(mut self, source: &str) -> Result<Self> {
513        let grammar = self.grammar_mut();
514        grammar.outline_query = Some(Query::new(grammar.ts_language, source)?);
515        Ok(self)
516    }
517
518    fn grammar_mut(&mut self) -> &mut Grammar {
519        Arc::get_mut(self.grammar.as_mut().unwrap()).unwrap()
520    }
521
522    pub fn with_lsp_adapter(mut self, lsp_adapter: Arc<dyn LspAdapter>) -> Self {
523        self.adapter = Some(lsp_adapter);
524        self
525    }
526
527    #[cfg(any(test, feature = "test-support"))]
528    pub fn set_fake_lsp_adapter(
529        &mut self,
530        fake_lsp_adapter: FakeLspAdapter,
531    ) -> mpsc::UnboundedReceiver<lsp::FakeLanguageServer> {
532        let (servers_tx, servers_rx) = mpsc::unbounded();
533        let adapter = Arc::new(fake_lsp_adapter);
534        self.fake_adapter = Some((servers_tx, adapter.clone()));
535        self.adapter = Some(adapter);
536        servers_rx
537    }
538
539    pub fn name(&self) -> Arc<str> {
540        self.config.name.clone()
541    }
542
543    pub fn line_comment_prefix(&self) -> Option<&str> {
544        self.config.line_comment.as_deref()
545    }
546
547    pub fn disk_based_diagnostic_sources(&self) -> &'static [&'static str] {
548        self.adapter.as_ref().map_or(&[] as &[_], |adapter| {
549            adapter.disk_based_diagnostic_sources()
550        })
551    }
552
553    pub fn disk_based_diagnostics_progress_token(&self) -> Option<&'static str> {
554        self.adapter
555            .as_ref()
556            .and_then(|adapter| adapter.disk_based_diagnostics_progress_token())
557    }
558
559    pub fn process_diagnostics(&self, diagnostics: &mut lsp::PublishDiagnosticsParams) {
560        if let Some(processor) = self.adapter.as_ref() {
561            processor.process_diagnostics(diagnostics);
562        }
563    }
564
565    pub fn label_for_completion(&self, completion: &lsp::CompletionItem) -> Option<CodeLabel> {
566        self.adapter
567            .as_ref()?
568            .label_for_completion(completion, self)
569    }
570
571    pub fn label_for_symbol(&self, name: &str, kind: lsp::SymbolKind) -> Option<CodeLabel> {
572        self.adapter.as_ref()?.label_for_symbol(name, kind, self)
573    }
574
575    pub fn highlight_text<'a>(
576        &'a self,
577        text: &'a Rope,
578        range: Range<usize>,
579    ) -> Vec<(Range<usize>, HighlightId)> {
580        let mut result = Vec::new();
581        if let Some(grammar) = &self.grammar {
582            let tree = grammar.parse_text(text, None);
583            let mut offset = 0;
584            for chunk in BufferChunks::new(text, range, Some(&tree), self.grammar.as_ref(), vec![])
585            {
586                let end_offset = offset + chunk.text.len();
587                if let Some(highlight_id) = chunk.syntax_highlight_id {
588                    if !highlight_id.is_default() {
589                        result.push((offset..end_offset, highlight_id));
590                    }
591                }
592                offset = end_offset;
593            }
594        }
595        result
596    }
597
598    pub fn brackets(&self) -> &[BracketPair] {
599        &self.config.brackets
600    }
601
602    pub fn path_suffixes(&self) -> &[String] {
603        &self.config.path_suffixes
604    }
605
606    pub fn should_autoclose_before(&self, c: char) -> bool {
607        c.is_whitespace() || self.config.autoclose_before.contains(c)
608    }
609
610    pub fn set_theme(&self, theme: &SyntaxTheme) {
611        if let Some(grammar) = self.grammar.as_ref() {
612            if let Some(highlights_query) = &grammar.highlights_query {
613                *grammar.highlight_map.lock() =
614                    HighlightMap::new(highlights_query.capture_names(), theme);
615            }
616        }
617    }
618
619    pub fn grammar(&self) -> Option<&Arc<Grammar>> {
620        self.grammar.as_ref()
621    }
622}
623
624impl Grammar {
625    fn parse_text(&self, text: &Rope, old_tree: Option<Tree>) -> Tree {
626        PARSER.with(|parser| {
627            let mut parser = parser.borrow_mut();
628            parser
629                .set_language(self.ts_language)
630                .expect("incompatible grammar");
631            let mut chunks = text.chunks_in_range(0..text.len());
632            parser
633                .parse_with(
634                    &mut move |offset, _| {
635                        chunks.seek(offset);
636                        chunks.next().unwrap_or("").as_bytes()
637                    },
638                    old_tree.as_ref(),
639                )
640                .unwrap()
641        })
642    }
643
644    pub fn highlight_map(&self) -> HighlightMap {
645        self.highlight_map.lock().clone()
646    }
647
648    pub fn highlight_id_for_name(&self, name: &str) -> Option<HighlightId> {
649        let capture_id = self
650            .highlights_query
651            .as_ref()?
652            .capture_index_for_name(name)?;
653        Some(self.highlight_map.lock().get(capture_id))
654    }
655}
656
657impl CodeLabel {
658    pub fn plain(text: String, filter_text: Option<&str>) -> Self {
659        let mut result = Self {
660            runs: Vec::new(),
661            filter_range: 0..text.len(),
662            text,
663        };
664        if let Some(filter_text) = filter_text {
665            if let Some(ix) = result.text.find(filter_text) {
666                result.filter_range = ix..ix + filter_text.len();
667            }
668        }
669        result
670    }
671}
672
673#[cfg(any(test, feature = "test-support"))]
674impl Default for FakeLspAdapter {
675    fn default() -> Self {
676        Self {
677            name: "the-fake-language-server",
678            capabilities: lsp::LanguageServer::full_capabilities(),
679            initializer: None,
680            disk_based_diagnostics_progress_token: None,
681            disk_based_diagnostics_sources: &[],
682        }
683    }
684}
685
686#[cfg(any(test, feature = "test-support"))]
687impl LspAdapter for FakeLspAdapter {
688    fn name(&self) -> LanguageServerName {
689        LanguageServerName(self.name.into())
690    }
691
692    fn fetch_latest_server_version(
693        &self,
694        _: Arc<dyn HttpClient>,
695    ) -> BoxFuture<'static, Result<Box<dyn 'static + Send + Any>>> {
696        unreachable!();
697    }
698
699    fn fetch_server_binary(
700        &self,
701        _: Box<dyn 'static + Send + Any>,
702        _: Arc<dyn HttpClient>,
703        _: Arc<Path>,
704    ) -> BoxFuture<'static, Result<PathBuf>> {
705        unreachable!();
706    }
707
708    fn cached_server_binary(&self, _: Arc<Path>) -> BoxFuture<'static, Option<PathBuf>> {
709        unreachable!();
710    }
711
712    fn process_diagnostics(&self, _: &mut lsp::PublishDiagnosticsParams) {}
713
714    fn disk_based_diagnostic_sources(&self) -> &'static [&'static str] {
715        self.disk_based_diagnostics_sources
716    }
717
718    fn disk_based_diagnostics_progress_token(&self) -> Option<&'static str> {
719        self.disk_based_diagnostics_progress_token
720    }
721}
722
723pub fn point_to_lsp(point: PointUtf16) -> lsp::Position {
724    lsp::Position::new(point.row, point.column)
725}
726
727pub fn point_from_lsp(point: lsp::Position) -> PointUtf16 {
728    PointUtf16::new(point.line, point.character)
729}
730
731pub fn range_to_lsp(range: Range<PointUtf16>) -> lsp::Range {
732    lsp::Range {
733        start: point_to_lsp(range.start),
734        end: point_to_lsp(range.end),
735    }
736}
737
738pub fn range_from_lsp(range: lsp::Range) -> Range<PointUtf16> {
739    let mut start = point_from_lsp(range.start);
740    let mut end = point_from_lsp(range.end);
741    if start > end {
742        mem::swap(&mut start, &mut end);
743    }
744    start..end
745}