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replace "modulo arithmetic" with "modular arithmetic" (#2088)

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Eisenwave
2023-06-24 05:42:15 +02:00
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@@ -13430,8 +13430,8 @@ Unsigned types support bit manipulation without surprises from sign bits.
##### Note ##### Note
Unsigned types can also be useful for modulo arithmetic. Unsigned types can also be useful for modular arithmetic.
However, if you want modulo arithmetic add However, if you want modular arithmetic add
comments as necessary noting the reliance on wraparound behavior, as such code comments as necessary noting the reliance on wraparound behavior, as such code
can be surprising for many programmers. can be surprising for many programmers.
@@ -13445,7 +13445,7 @@ can be surprising for many programmers.
##### Reason ##### Reason
Because most arithmetic is assumed to be signed; Because most arithmetic is assumed to be signed;
`x - y` yields a negative number when `y > x` except in the rare cases where you really want modulo arithmetic. `x - y` yields a negative number when `y > x` except in the rare cases where you really want modular arithmetic.
##### Example ##### Example
@@ -13475,7 +13475,7 @@ but if you had seen `us - (s + 2)` or `s += 2; ...; us - s`, would you reliably
##### Exception ##### Exception
Use unsigned types if you really want modulo arithmetic - add Use unsigned types if you really want modular arithmetic - add
comments as necessary noting the reliance on overflow behavior, as such code comments as necessary noting the reliance on overflow behavior, as such code
is going to be surprising for many programmers. is going to be surprising for many programmers.
@@ -13534,7 +13534,7 @@ Incrementing a value beyond a maximum value can lead to memory corruption and un
##### Exception ##### Exception
Use unsigned types if you really want modulo arithmetic. Use unsigned types if you really want modular arithmetic.
**Alternative**: For critical applications that can afford some overhead, use a range-checked integer and/or floating-point type. **Alternative**: For critical applications that can afford some overhead, use a range-checked integer and/or floating-point type.
@@ -13559,7 +13559,7 @@ Decrementing a value beyond a minimum value can lead to memory corruption and un
##### Exception ##### Exception
Use unsigned types if you really want modulo arithmetic. Use unsigned types if you really want modular arithmetic.
##### Enforcement ##### Enforcement
@@ -13609,7 +13609,7 @@ This also applies to `%`.
##### Reason ##### Reason
Choosing `unsigned` implies many changes to the usual behavior of integers, including modulo arithmetic, Choosing `unsigned` implies many changes to the usual behavior of integers, including modular arithmetic,
can suppress warnings related to overflow, can suppress warnings related to overflow,
and opens the door for errors related to signed/unsigned mixes. and opens the door for errors related to signed/unsigned mixes.
Using `unsigned` doesn't actually eliminate the possibility of negative values. Using `unsigned` doesn't actually eliminate the possibility of negative values.
@@ -13631,7 +13631,7 @@ Consider:
auto a = area(height, 2); // if the input is -2 a becomes 4294967292 auto a = area(height, 2); // if the input is -2 a becomes 4294967292
Remember that `-1` when assigned to an `unsigned int` becomes the largest `unsigned int`. Remember that `-1` when assigned to an `unsigned int` becomes the largest `unsigned int`.
Also, since unsigned arithmetic is modulo arithmetic the multiplication didn't overflow, it wrapped around. Also, since unsigned arithmetic is modular arithmetic the multiplication didn't overflow, it wrapped around.
##### Example ##### Example