133 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			V
		
	
	
			
		
		
	
	
			133 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			V
		
	
	
// Copyright (c) 2019-2022 Alexander Medvednikov. All rights reserved.
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// Use of this source code is governed by an MIT license
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// that can be found in the LICENSE file.
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module builtin
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fn (a any) toString()
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[noreturn]
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pub fn panic(s string) {
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	eprintln('V panic: $s\n$js_stacktrace()')
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	exit(1)
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}
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// IError holds information about an error instance
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pub interface IError {
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	// >> Hack to allow old style custom error implementations
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	// TODO: remove once deprecation period for `IError` methods has ended
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	msg string
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	code int // <<
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	msg() string
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	code() int
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}
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pub fn (err IError) str() string {
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	return match err {
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		None__ {
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			'none'
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		}
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		Error {
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			err.msg()
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		}
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		MessageError {
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			err.msg()
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		}
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		else {
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			// >> Hack to allow old style custom error implementations
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			// TODO: remove once deprecation period for `IError` methods has ended
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			old_error_style := unsafe { voidptr(&err.msg) != voidptr(&err.code) } // if fields are not defined (new style) they don't have an offset between them
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			if old_error_style {
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				'$err.type_name(): $err.msg'
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			} else {
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				// <<
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				'$err.type_name(): $err.msg()'
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			}
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		}
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	}
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}
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// Error is the empty default implementation of `IError`.
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pub struct Error {}
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pub fn (err Error) msg() string {
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	return ''
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}
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pub fn (err Error) code() int {
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	return 0
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}
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// MessageError is the default implementation of the `IError` interface that is returned by the `error()` function
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struct MessageError {
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pub:
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	msg  string
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	code int
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}
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pub fn (err MessageError) msg() string {
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	return err.msg
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}
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pub fn (err MessageError) code() int {
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	return err.code
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}
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pub const none__ = IError(&None__{})
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struct None__ {
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	Error
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}
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fn (_ None__) str() string {
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	return 'none'
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}
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pub struct Option {
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	state byte
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	err   IError = none__
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}
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pub fn (o Option) str() string {
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	if o.state == 0 {
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		return 'Option{ ok }'
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	}
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	if o.state == 1 {
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		return 'Option{ none }'
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	}
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	return 'Option{ error: "$o.err" }'
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}
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// trace_error prints to stderr a string and a backtrace of the error
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fn trace_error(x string) {
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	eprintln('> ${@FN} | $x')
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}
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// error returns a default error instance containing the error given in `message`.
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// Example: if ouch { return error('an error occurred') }
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[inline]
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pub fn error(message string) IError {
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	// trace_error(message)
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	return &MessageError{
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		msg: message
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	}
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}
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// error_with_code returns a default error instance containing the given `message` and error `code`.
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// Example: if ouch { return error_with_code('an error occurred', 1) }
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[inline]
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pub fn error_with_code(message string, code int) IError {
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	// trace_error('$message | code: $code')
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	return &MessageError{
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		msg: message
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		code: code
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	}
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}
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// free allows for manually freeing memory allocated at the address `ptr`.
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// However, this is a no-op on JS backend
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[unsafe]
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pub fn free(ptr voidptr) {
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	_ := ptr
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}
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