src/tint/lang/wgsl/inspector/scalar.h

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#ifndef SRC_TINT_LANG_WGSL_INSPECTOR_SCALAR_H_
#define SRC_TINT_LANG_WGSL_INSPECTOR_SCALAR_H_

#include <cstdint>

namespace tint::inspector {

/// Contains a literal scalar value
class Scalar {
  public:
    /// Null Constructor
    Scalar();
    /// @param val literal scalar value to contain
    explicit Scalar(bool val);
    /// @param val literal scalar value to contain
    explicit Scalar(uint32_t val);
    /// @param val literal scalar value to contain
    explicit Scalar(int32_t val);
    /// @param val literal scalar value to contain
    explicit Scalar(float val);

    /// @returns true if this is a null
    bool IsNull() const;
    /// @returns true if this is a bool
    bool IsBool() const;
    /// @returns true if this is a unsigned integer.
    bool IsU32() const;
    /// @returns true if this is a signed integer.
    bool IsI32() const;
    /// @returns true if this is a float.
    bool IsFloat() const;

    /// @returns scalar value if bool, otherwise undefined behaviour.
    bool AsBool() const;
    /// @returns scalar value if unsigned integer, otherwise undefined behaviour.
    uint32_t AsU32() const;
    /// @returns scalar value if signed integer, otherwise undefined behaviour.
    int32_t AsI32() const;
    /// @returns scalar value if float, otherwise undefined behaviour.
    float AsFloat() const;

  private:
    typedef enum {
        kNull,
        kBool,
        kU32,
        kI32,
        kFloat,
    } Type;

    typedef union {
        bool b;
        uint32_t u;
        int32_t i;
        float f;
    } Value;

    Type type_;
    Value value_;
};

}  // namespace tint::inspector

#endif  // SRC_TINT_LANG_WGSL_INSPECTOR_SCALAR_H_