Convenience methods wrap up existing functionality in a more convenient way. The work done by a convenience method varies widely:
std::path::Path
type
provides methods like stat
`staton
` on Path
`Paths that simply invoke the corresponding function in
std::io::fs`.str
`strtype provides a
.len()convenience method which is also expressible as
.as_bytes().len(). Sometimes the conversion is more complex: the
strmodule also provides
from_chars`, which encapsulates a simple use of iterators.&str
`&strs provide a
connectas well as a special case,
concat, that is expressible using
connectwith a fixed separator of
""`.Providing more efficient special cases. The connect
`connectand
` and concat
`concatexample also applies here: singling out
concat` as a special case allows for a more
efficient implementation.
Note, however, that the connect
`connectmethod actually detects the special case internally and invokes
concat`. Usually, it is not necessary to add a public
convenience method just for efficiency gains; there should also be a
conceptual reason to add it, e.g. because it is such a common special case.
It is tempting to add convenience methods in a one-off, haphazard way as common use patterns emerge. Avoid this temptation, and instead design small, coherent sets of convenience methods that are easy to remember:
_str
`_strvariants of methods that provide a
stroutput, instead ensure that the normal output type of methods is easily convertible to
str`.Path
`PathAPI mentioned above includes a small selection of the most common filesystem operations that take a
Path`
argument. If one convenience method strongly suggests the existence of others,
consider adding the whole group.