O bloco with e os gerenciadores de contexto | Live de Python #302

Nesta live, vamos explorar os Gerenciadores de Contexto em Python, uma das ferramentas mais poderosas para o gerenciamento de recursos e controle de fluxo. Vamos entender como o bloco with funciona, o protocolo por trás dele (com os métodos __enter__ e __exit__), e como podemos usar a biblioteca contextlib para simplificar nossa vida. Também veremos como o gerenciamento assíncrono entra em cena com o async with, além de exemplos práticos e boas práticas para aplicar em seus projetos.

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# Referencias

[1] “3. Data model - Asynchronous Context Managers”, Python documentation. Acesso em: 30 de outubro de 2025. [Online]. Disponível em: https://docs.python.org/3/reference/datamodel.html#asynchronous-context-managers
[2] “3. Data model - With Statement Context Managers”, Python documentation. Acesso em: 30 de outubro de 2025. [Online]. Disponível em: https://docs.python.org/3/reference/datamodel.html#with-statement-context-managers
[3] “8. Compound statements”, Python documentation. Acesso em: 30 de outubro de 2025. [Online]. Disponível em: https://docs.python.org/3/reference/compound_stmts.html
[4] “10. Full Grammar specification”, Python documentation. Acesso em: 2 de novembro de 2025. [Online]. Disponível em: https://docs.python.org/3/reference/grammar.html
[5] “Built-in Types”, Python documentation. Acesso em: 30 de outubro de 2025. [Online]. Disponível em: https://docs.python.org/3/library/stdtypes.html
[6] “contextlib — Utilities for with-statement contexts”, Python documentation. Acesso em: 30 de outubro de 2025. [Online]. Disponível em: https://docs.python.org/3/library/contextlib.html
[7] “Contexto”, Michaelis On-Line. Acesso em: 31 de outubro de 2025. [Online]. Disponível em: https://michaelis.uol.com.br/moderno-portugues/busca/portugues-brasileiro/contexto/
[8] “PEP 343 – The ‘with’ Statement | peps.python.org”, Python Enhancement Proposals (PEPs). Acesso em: 31 de outubro de 2025. [Online]. Disponível em: https://peps.python.org/pep-0343/
[9] “PEP 617 – New PEG parser for CPython | peps.python.org”, Python Enhancement Proposals (PEPs). Acesso em: 2 de novembro de 2025. [Online]. Disponível em: https://peps.python.org/pep-0617/
[10] “PEP 806 – Mixed sync/async context managers with precise async marking | peps.python.org”, Python Enhancement Proposals (PEPs). Acesso em: 31 de outubro de 2025. [Online]. Disponível em: https://peps.python.org/pep-0806/
[11] “Defer - Learn Swift By Examples”. Acesso em: 1º de novembro de 2025. [Online]. Disponível em: https://learn-swift.com/defer/
[12] “Defer, Panic, and Recover - The Go Programming Language”. Acesso em: 1º de novembro de 2025. [Online]. Disponível em: https://go.dev/blog/defer-panic-and-recover
[13] “exceptions - Documentation for Ruby 3.5”. Acesso em: 1º de novembro de 2025. [Online]. Disponível em: https://docs.ruby-lang.org/en/master/syntax/exceptions_rdoc.html
[14] dotnet-bot, “IDisposable Interface (System)”. Acesso em: 1º de novembro de 2025. [Online]. Disponível em: https://learn.microsoft.com/en-us/dotnet/api/system.idisposable?view=net-9.0
[15] “The try-with-resources Statement (The Java™ Tutorials - Essential Java Classes - Exceptions)”. Acesso em: 1º de novembro de 2025. [Online]. Disponível em: https://docs.oracle.com/javase/tutorial/essential/exceptions/tryResourceClose.html Receive SMS online on sms24.me

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