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//! Panic support for core |
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//! |
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-//! The core library cannot define panicking, but it does *declare* panicking. This |
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-//! means that the functions inside of core are allowed to panic, but to be |
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+//! In core, panicking is always done with a message, resulting in a core::panic::PanicInfo |
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+//! containing a fmt::Arguments. In std, however, panicking can be done with panic_any, which throws |
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+//! a Box containing any type of value. Because of this, std::panic::PanicInfo is a |
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+//! different type, which contains a &dyn Any instead of a fmt::Arguments. |
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+//! std's panic handler will convert the fmt::Arguments to a &dyn Any containing either a |
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+//! &'static str or String containing the formatted message. |
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+//! |
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+//! The core library cannot define any panic handler, but it can invoke it. |
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+//! This means that the functions inside of core are allowed to panic, but to be |
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//! useful an upstream crate must define panicking for core to use. The current |
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//! interface for panicking is: |
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//! |
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//! # { loop {} } |
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//! ``` |
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//! |
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-//! This definition allows for panicking with any general message, but it does not |
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-//! allow for failing with a `Box` value. (`PanicInfo` just contains a `&(dyn Any + Send)`, |
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-//! for which we fill in a dummy value in `PanicInfo::internal_constructor`.) |
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-//! The reason for this is that core is not allowed to allocate. |
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-//! |
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//! This module contains a few other panicking functions, but these are just the |
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//! necessary lang items for the compiler. All panics are funneled through this |
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//! one function. The actual symbol is declared through the `#[panic_handler]` attribute. |