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std.algorithm.searching.count_until - multiple declarations
- Function countUntil
- Function countUntil
Function countUntil
Counts elements in the given
forward range
until the given predicate is true for one of the given needles
Prototypes
ptrdiff_t countUntil(alias pred, R, Rs...)( R haystack, Rs needles ) if (isForwardRange!R && Rs.length > 0 && isForwardRange!(Rs[0]) == isInputRange!(Rs[0]) && is(typeof(startsWith!pred(haystack, needles[0]))) && (Rs.length == 1 || is(typeof(countUntil!pred(haystack, needles[1..__dollar]))))); ptrdiff_t countUntil(alias pred, R, N)( R haystack, N needle ) if (isInputRange!R && is(typeof(binaryFun!pred(haystack.front, needle)) : bool));
Parameters
| Name | Description |
|---|---|
| pred | The predicate for determining when to stop counting. |
| haystack | The input range to be counted. |
| needles | Either a single element, or a
forward range
of elements, to be evaluated in turn against each
element in |
Returns
The number of elements which must be popped from the front of
haystackstartsWith!pred(haystack, needles)true. If
startsWith!pred(haystack, needles)true for any element in
haystack-1 is returned.
Example
assert(countUntil("hello world", "world") == 6);
assert(countUntil("hello world", 'r') == 8);
assert(countUntil("hello world", "programming") == -1);
assert(countUntil("日本語", "本語") == 1);
assert(countUntil("日本語", '語') == 2);
assert(countUntil("日本語", "五") == -1);
assert(countUntil("日本語", '五') == -1);
assert(countUntil([0, 7, 12, 22, 9], [12, 22]) == 2);
assert(countUntil([0, 7, 12, 22, 9], 9) == 4);
assert(countUntil!"a > b"([0, 7, 12, 22, 9], 20) == 3);
Function countUntil
Similar to the previous overload of countUntilpred.
Prototype
ptrdiff_t countUntil(alias pred, R)( R haystack ) if (isInputRange!R && is(typeof(unaryFun!pred(haystack.front)) : bool));
Parameters
| Name | Description |
|---|---|
| pred | Predicate to when to stop counting. |
| haystack | An input range of elements to be counted. |
Returns
The number of elements which must be popped from haystackpred(haystack.front) is true.
Example
import std.ascii : isDigit; import std.uni : isWhite; assert(countUntil!(std.uni.isWhite)("hello world") == 5); assert(countUntil!(std.ascii.isDigit)("hello world") == -1); assert(countUntil!"a > 20"([0, 7, 12, 22, 9]) == 3);