//! # `console_error_panic_hook`
//!
//! [](https://docs.rs/console_error_panic_hook/)
//! [](https://crates.io/crates/console_error_panic_hook)
//! [](https://crates.io/crates/console_error_panic_hook)
//! [](https://travis-ci.org/rustwasm/console_error_panic_hook)
//!
//! This crate lets you debug panics on `wasm32-unknown-unknown` by providing a
//! panic hook that forwards panic messages to
//! [`console.error`](https://developer.mozilla.org/en-US/docs/Web/API/Console/error).
//!
//! When an error is reported with `console.error`, browser devtools and node.js
//! will typically capture a stack trace and display it with the logged error
//! message.
//!
//! Without `console_error_panic_hook` you just get something like *RuntimeError: Unreachable executed*
//!
//! Browser:
//! 
//!
//! Node:
//! 
//!
//! With this panic hook installed you will see the panic message
//!
//! Browser:
//! 
//!
//! Node:
//! 
//!
//! ## Usage
//!
//! There are two ways to install this panic hook.
//!
//! First, you can set the hook yourself by calling `std::panic::set_hook` in
//! some initialization function:
//!
//! ```
//! extern crate console_error_panic_hook;
//! use std::panic;
//!
//! fn my_init_function() {
//! panic::set_hook(Box::new(console_error_panic_hook::hook));
//!
//! // ...
//! }
//! ```
//!
//! Alternatively, use `set_once` on some common code path to ensure that
//! `set_hook` is called, but only the one time. Under the hood, this uses
//! `std::sync::Once`.
//!
//! ```
//! extern crate console_error_panic_hook;
//!
//! struct MyBigThing;
//!
//! impl MyBigThing {
//! pub fn new() -> MyBigThing {
//! console_error_panic_hook::set_once();
//!
//! MyBigThing
//! }
//! }
//! ```
//!
//! ## Error.stackTraceLimit
//!
//! Many browsers only capture the top 10 frames of a stack trace. In rust programs this is less likely to be enough. To see more frames, you can set the non-standard value `Error.stackTraceLimit`. For more information see the [MDN Web Docs](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Microsoft_Extensions/Error.stackTraceLimit) or [v8 docs](https://v8.dev/docs/stack-trace-api).
//!
extern crate cfg_if;
use panic;
cfg_if!
/// A panic hook for use with
/// [`std::panic::set_hook`](https://doc.rust-lang.org/nightly/std/panic/fn.set_hook.html)
/// that logs panics into
/// [`console.error`](https://developer.mozilla.org/en-US/docs/Web/API/Console/error).
///
/// On non-wasm targets, prints the panic to `stderr`.
/// Set the `console.error` panic hook the first time this is called. Subsequent
/// invocations do nothing.