Source/WebGPU/WGSL/SourceSpan.h

/*
 * Copyright (C) 2022 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
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 * 1. Redistributions of source code must retain the above copyright
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
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 */

#pragma once

namespace WGSL {

struct SourcePosition {
    unsigned line;
    unsigned lineOffset;
    unsigned offset;
};

struct SourceSpan {
    unsigned line;
    unsigned lineOffset;
    unsigned offset;
    unsigned length;

    static constexpr SourceSpan empty() { return { 0, 0, 0, 0 }; }

    constexpr SourceSpan(unsigned line, unsigned lineOffset, unsigned offset, unsigned length)
        : line(line)
        , lineOffset(lineOffset)
        , offset(offset)
        , length(length)
    { }

    constexpr SourceSpan(SourcePosition start, SourcePosition end)
        : SourceSpan(start.line, start.lineOffset, start.offset, end.offset - start.offset)
    { }

    friend constexpr bool operator==(const SourceSpan&, const SourceSpan&) = default;
};

}