semvec/pypi-packages huggingface dataset:
prettyerr 0.0.4
Pretty error messages
Requires Python: >=3.10

# Pretty Err

[![PyPI version](https://img.shields.io/pypi/v/prettyerr.svg)](https://pypi.org/project/prettyerr/)
[![Python versions](https://img.shields.io/pypi/pyversions/prettyerr.svg)](https://pypi.org/project/prettyerr/)
[![CI](https://github.com/david-andrew/prettyerr/actions/workflows/sync-dewy-error-reporting.yml/badge.svg)](https://github.com/david-andrew/prettyerr/actions/workflows/sync-dewy-error-reporting.yml)

A simple library for printing modern, source-annotated error messages.

## Features
- source span annotation
- color output
- multiple non-overlapping spans
- zero-width spans

## Install
```
pip install prettyerr
```

## Quickstart
Print out an error report for some example source code

```python
from prettyerr import Error, Pointer, Span, SrcFile

# example source code
src = """\
const repeat = (message:string, times:int) :> string => {
    return message * times
}
result = repeat("hello", "3")
printl(result)
"""

# Locate spans to highlight (.index() here is just for simplicity)
repeat_start = src.index('repeat(')
bad_arg_start = src.index('"3"')
times_span = Span(repeat_start, repeat_start + len('repeat'))
bad_arg_span = Span(bad_arg_start, bad_arg_start + len('"3"'))

# Build and print the error report
report = Error(
    SrcFile.from_text(src, "path/to/example.lang"),
    title="type mismatch for argument `times`",
    pointer_messages=[
        Pointer(span=times_span, message="`repeat` function's second argument `times` expects an 'int'"),
        Pointer(span=bad_arg_span, message="argument given is type 'string'"),
    ],
    hint='Consider changing string literal "3" to integer 3',
)
print(report)
```

This generates the following error report
```
Error: type mismatch for argument `times`

    ╭─[path/to/example.lang:4:10]
  4 | result = repeat("hello", "3")
    ·          ──┬───          ─┬─
    ·            │              ╰─ argument given is type 'string'
    ·            ╰─ `repeat` function's second argument `times` expects an 'int'
    ╰───
  help: Consider changing string literal "3" to integer 3
```

## API at a glance
- `SrcFile.from_text(body, path=None)`
- `Span(start, stop)` (stop-exclusive)
- `Pointer(span=Span(...) | list[Span], message=..., placement=None, color=None)`
- Report types: `Error`, `Warning`, `Info`, `Hint`
- Common fields: `title`, `message`, `pointer_messages`, `hint`, `use_color`

## Tips
- Disable ANSI colors with `use_color=False`.
- Raise an exception with `Error(...).throw()` (raises `ReportException`).