stride

uint stride(S)(auto  ref  S str,  size_t index) if (is(S :  const  char[])  ||
    (isRandomAccessRange!S &&  is(immutable  ElementType!S ==  immutable  char)))

Calculate the length of the UTF sequence starting at index in str.

Parameters

`str`	input range of UTF code units. Must be random access if `index` is passed
`index`	starting index of UTF sequence (default: `0`)

Returns

The number of code units in the UTF sequence. For UTF-8, this is a

value between 1 and 4 (as per RFC 3629, section 3). For UTF-16, it is either 1 or 2. For UTF-32, it is always 1.

Throws

May throw a UTFException if str[index] is not the start of a

valid UTF sequence.

Note

stride will only analyze the first str[index] element. It

will not fully verify the validity of the UTF sequence, nor even verify the presence of the sequence: it will not actually guarantee that

index + stride(str, index) <= str.length.

uint stride(S)(auto  ref  S str) if (is(S :  const  char[])  ||
    (isInputRange!S &&  is(immutable  ElementType!S ==  immutable  char)))

Ditto

uint stride(S)(auto  ref  S str,  size_t index) if (is(S :  const  wchar[])  ||
    (isRandomAccessRange!S &&  is(immutable  ElementType!S ==  immutable  wchar)))

Ditto

fnuint stride(S)(auto ref S str) if (is(S : const wchar[])) @safe pure

Ditto

uint stride(S)(auto  ref  S str) if (isInputRange!S &&  is(immutable  ElementType!S ==  immutable  wchar)  &&
    !is(S :  const  wchar[]))

Ditto

uint stride(S)(auto  ref  S str,  size_t index =  0) if (is(S :  const  dchar[])  ||
    (isInputRange!S &&  is(immutable  ElementEncodingType!S ==  immutable  dchar)))

Ditto