safety.md

Safety

Dangling references

This library's syntax explicitly forces you to choose between std::move()-ing or std::ref()-ing existing variables into adaptors.¹ This avoids unintendedly creating dangling references.

See the examples.

Undefined behaviour

An unsorted list of instances where usage patterns that result in standard library undefined behaviour are ill-formed (and thus prevented) with this library:

• Assigning through range adaptors that would invalidate those range adaptors in non-obvious ways (e.g. changing the element underlying a filter adaptor so that it no longer satisfies the predicat).
• Some (but not all) examples of inadvertantly creating a multi-pass adaptor that violates the multi-pass guarantee. See also tradeoffs.

Many of these have examples on the examples page.

Footnotes

1. Note that we are not technically storing std::reference_wrapper, we are just using std::ref as a marker for opting in to the indirection. ↩