From Jason Turner

[bitmask.types]

C++14 → C++17 2.0 KB 23 lines
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Archived: C++14 | C++17
Markdown: C++14 | C++17
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  1. tmp/tmp90rn_3ih/{from.md → to.md} +9 -10
tmp/tmp90rn_3ih/{from.md → to.md} RENAMED
@@ -7,20 +7,19 @@ operators, as an integer type, or as a `bitset` ([[template.bitset]]).
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  The bitmask type *bitmask* can be written:
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  ``` cpp
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  // For exposition only.
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- // int_type is an integral type capable of
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- // representing all values of the bitmask type.
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  enum bitmask : int_type {
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- V0 = 1 << 0, V1 = 1 << 1, V2 = 1 << 2, V3 = 1 << 3, .....
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  };
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- constexpr bitmask C0(V0{});
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- constexpr bitmask C1(V1{});
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- constexpr bitmask C2(V2{});
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- constexpr bitmask C3(V3{});
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  .....
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  constexpr bitmask{} operator&(bitmask{} X, bitmask{} Y) {
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  return static_cast<bitmask{}>(
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  static_cast<int_type>(X) & static_cast<int_type>(Y));
@@ -45,14 +44,14 @@ bitmask{}& operator|=(bitmask{}& X, bitmask{} Y) {
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  bitmask{}& operator^=(bitmask{}& X, bitmask{} Y) {
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  X = X ^ Y; return X;
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  }
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  ```
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- Here, the names *C0*, *C1*, etc. represent *bitmask elements* for this
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  particular bitmask type. All such elements have distinct, nonzero values
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- such that, for any pair *Ci* and *Cj* where *i* != *j*, *Ci* & *Ci* is
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- nonzero and *Ci* & *Cj* is zero. Additionally, the value 0 is used to
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  represent an *empty bitmask*, in which no bitmask elements are set.
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  The following terms apply to objects and values of bitmask types:
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  - To *set* a value *Y* in an object *X* is to evaluate the expression
 
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  The bitmask type *bitmask* can be written:
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  ``` cpp
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  // For exposition only.
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+ // int_type is an integral type capable of representing all values of the bitmask type.
 
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  enum bitmask : int_type {
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+ V₀ = 1 << 0, V₁ = 1 << 1, V₂ = 1 << 2, V₃ = 1 << 3, .....
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  };
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+ inline constexpr bitmask C₀(V₀{});
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+ inline constexpr bitmask C₁(V₁{});
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+ inline constexpr bitmask C₂(V₂{});
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+ inline constexpr bitmask C₃(V₃{});
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  .....
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  constexpr bitmask{} operator&(bitmask{} X, bitmask{} Y) {
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  return static_cast<bitmask{}>(
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  static_cast<int_type>(X) & static_cast<int_type>(Y));
 
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  bitmask{}& operator^=(bitmask{}& X, bitmask{} Y) {
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  X = X ^ Y; return X;
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  }
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  ```
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+ Here, the names `C₀`, `C₁`, etc. represent *bitmask elements* for this
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  particular bitmask type. All such elements have distinct, nonzero values
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+ such that, for any pair `Cᵢ` and `Cⱼ` where i ≠ j, `C_i & C_i` is
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+ nonzero and `C_i & C_j` is zero. Additionally, the value `0` is used to
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  represent an *empty bitmask*, in which no bitmask elements are set.
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  The following terms apply to objects and values of bitmask types:
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  - To *set* a value *Y* in an object *X* is to evaluate the expression