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Exception handling

Avoid exception handling in conversions as long as possible, because it reduces clarity and can hide issues in the code.

c.try_

Experimental feature

It was added on Feb 21, 2024 and may be stabilized ~ in half a year.

c.try_(conv).except_(exc_def, value, re_raise_if=None) conversion wrapper allows to handle exceptions:

  • conv: a conversion, which is expected to raise an exception
  • exc_def: exception class or tuple of exception classes to be caught
  • re_raise_if (optional): if it evaluates to true, the caught exception is re-raised
from convtools import conversion as c

converter = (
    c.iter(
        c.try_(c.item(0) / c.item(1))
        .except_(ZeroDivisionError, value=c.this, re_raise_if=c.item(0) == 0)
        .except_(TypeError, None)
    )
    .as_type(list)
    .gen_converter(debug=True)
)

assert converter([(1, 2), (3, 0), (4, "abc")]) == [0.5, (3, 0), None]

def except_(data_):
    try:
        return data_[0] / data_[1]
    except ZeroDivisionError as exc_:
        if data_[0] == 0:
            raise
        return data_
    except TypeError as exc_:
        return None

def converter(data_):
    try:
        return [except_(i) for i in data_]
    except __exceptions_to_dump_sources:
        __convtools__code_storage.dump_sources()
        raise