22 lines
1.3 KiB
Markdown
22 lines
1.3 KiB
Markdown
|
[](https://github.com/dart-lang/tools/actions/workflows/source_span.yaml)
|
||
|
|
[](https://pub.dev/packages/source_span)
|
||
|
|
[](https://pub.dev/packages/source_span/publisher)
|
||
|
|
|
||
|
|
## About this package
|
||
|
|
|
||
|
|
`source_span` is a library for tracking locations in source code. It's designed
|
||
|
|
to provide a standard representation for source code locations and spans so that
|
||
|
|
disparate packages can easily pass them among one another, and to make it easy
|
||
|
|
to generate human-friendly messages associated with a given piece of code.
|
||
|
|
|
||
|
|
The most commonly-used class is the package's namesake, `SourceSpan`. It
|
||
|
|
represents a span of characters in some source file, and is often attached to an
|
||
|
|
object that has been parsed to indicate where it was parsed from. It provides
|
||
|
|
access to the text of the span via `SourceSpan.text` and can be used to produce
|
||
|
|
human-friendly messages using `SourceSpan.message()`.
|
||
|
|
|
||
|
|
When parsing code from a file, `SourceFile` is useful. Not only does it provide
|
||
|
|
an efficient means of computing line and column numbers, `SourceFile.span()`
|
||
|
|
returns special `FileSpan`s that are able to provide more context for their
|
||
|
|
error messages.
|