| Value | Meaning |
|---|---|
| assumeJagged | When transversed, the elements of a range of ranges are assumed to have different lengths (e.g. a jagged array). |
| enforceNotJagged | The transversal enforces that the elements of a range of ranges have all the same length (e.g. an array of arrays, all having the same length). Checking is done once upon construction of the transversal range. |
| assumeNotJagged | The transversal assumes, without verifying, that the elements of a range of ranges have all the same length. This option is useful if checking was already done from the outside of the range. |
import std.algorithm.comparison : equal; import std.exception : assertThrown; auto arr = [[1, 2], [3, 4, 5]]; auto r1 = arr.frontTransversal!(TransverseOptions.assumeJagged); assert(r1.equal([1, 3])); // throws on construction assertThrown!Exception(arr.frontTransversal!(TransverseOptions.enforceNotJagged)); auto r2 = arr.frontTransversal!(TransverseOptions.assumeNotJagged); assert(r2.equal([1, 3])); // either assuming or checking for equal lengths makes // the result a random access range assert(r2[0] == 1); static assert(!__traits(compiles, r1[0]));
Options for the FrontTransversal and Transversal ranges (below).