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-module(safely). |
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%% This module preserves the return types of a `catch' statement, |
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%% but doesn't silently convert `throw's to normal values. |
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%% The issue is that throws have different semantics than errors: |
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%% https://erlang.org/doc/reference_manual/expressions.html#catch-and-throw, |
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%% so a throw is actually a control flow escape, while an error is an actual crash. |
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%% If it is an error, we want the stacktrace, if not, we don't. |
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%% For more information, see usage in test/safely_SUITE.erl |
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-include("safely.hrl"). |
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-include_lib("kernel/include/logger.hrl"). |
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-ifdef(TEST). |
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-export([apply/2, apply/3]). |
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-endif. |
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-export([apply_and_log/3, apply_and_log/4]). |
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-ignore_xref([apply_and_log/4]). |
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-type error_class() :: error | exit | throw. |
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-type error_info() :: #{class => error_class(), reason => term(), stacktrace => [term()]}. |
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-type exception() :: {exception, error_info()}. |
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-export_type([exception/0]). |
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-define(MATCH_EXCEPTIONS_DO_LOG(F, Context), |
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try F catch |
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error:R:S -> |
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Info = #{class => error, reason => R, stacktrace => S}, |
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?LOG_ERROR(maps:merge(Context, Info)), |
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{exception, Info}; |
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throw:R -> |
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Info = #{class => throw, reason => R}, |
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?LOG_ERROR(maps:merge(Context, Info)), |
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{exception, Info}; |
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exit:R:S -> |
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Info = #{class => exit, reason => R, stacktrace => S}, |
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?LOG_ERROR(maps:merge(Context, Info)), |
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{exception, Info} |
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end). |
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-ifdef(TEST). |
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-spec apply(fun((...) -> A), [term()]) -> A | exception(). |
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apply(Function, Args) when is_function(Function), is_list(Args) -> |
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?SAFELY(erlang:apply(Function, Args)). |
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-spec apply(atom(), atom(), [term()]) -> term() | exception(). |
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apply(Module, Function, Args) when is_atom(Function), is_list(Args) -> |
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?SAFELY(erlang:apply(Module, Function, Args)). |
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-endif. |
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-spec apply_and_log(fun((...) -> A), [term()], map()) -> A | exception(). |
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apply_and_log(Function, Args, Context) |
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when is_function(Function), is_list(Args), is_map(Context) -> |
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?MATCH_EXCEPTIONS_DO_LOG(erlang:apply(Function, Args), Context). |
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-spec apply_and_log(atom(), atom(), [term()], map()) -> term() | exception(). |
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apply_and_log(Module, Function, Args, Context) |
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when is_atom(Function), is_list(Args), is_map(Context) -> |
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:-( |
?MATCH_EXCEPTIONS_DO_LOG(erlang:apply(Module, Function, Args), Context). |