Overuse of try/catch

Python follows the principle better to ask for forgiveness than permission, which in practice means using try/except blocks with type checking on the error. In Julia the preference is to avoid the error using an initial check.

Anti-pattern

Overuse of constructs such as:

try
    myfunction()
catch e
    if isa(e, DomainError)
        response()
    else
        rethrow()
    end
end

Though the above is far preferable to the below, which risks triggering a desired response for the wrong error.

try
    myfunction()
catch
    response()
end

Best practice

if condition()
    myfunction()
else
    response()
end