Struct cxx::CxxString [−][src]
#[repr(C)]pub struct CxxString { /* fields omitted */ }
Expand description
Binding to C++ std::string
.
Invariants
As an invariant of this API and the static analysis of the cxx::bridge
macro, in Rust code we can never obtain a CxxString
by value. C++’s string
requires a move constructor and may hold internal pointers, which is not
compatible with Rust’s move behavior. Instead in Rust code we will only ever
look at a CxxString through a reference or smart pointer, as in &CxxString
or UniquePtr<CxxString>
.
Implementations
CxxString
is not constructible via new
. Instead, use the
let_cxx_string!
macro.
Returns the length of the string in bytes.
Matches the behavior of C++ std::string::size.
Returns true if self
has a length of zero bytes.
Matches the behavior of C++ std::string::empty.
Returns a byte slice of this string’s contents.
Produces a pointer to the first character of the string.
Matches the behavior of C++ std::string::data.
Note that the return type may look like const char *
but is not a
const char *
in the typical C sense, as C++ strings may contain
internal null bytes. As such, the returned pointer only makes sense as a
string in combination with the length returned by len()
.
Validates that the C++ string contains UTF-8 data and produces a view of it as a Rust &str, otherwise an error.
This is supported on crate feature alloc
only.
alloc
only.If the contents of the C++ string are valid UTF-8, this function returns a view as a Cow::Borrowed &str. Otherwise replaces any invalid UTF-8 sequences with the U+FFFD replacement character and returns a Cow::Owned String.
Removes all characters from the string.
Matches the behavior of C++ std::string::clear.
Note: unlike the guarantee of Rust’s std::string::String::clear
,
the C++ standard does not require that capacity is unchanged by this
operation. In practice existing implementations do not change the
capacity but all pointers, references, and iterators into the string
contents are nevertheless invalidated.
Ensures that this string’s capacity is at least additional
bytes
larger than its length.
The capacity may be increased by more than additional
bytes if it
chooses, to amortize the cost of frequent reallocations.
The meaning of the argument is not the same as
std::string::reserve in C++. The C++ standard library and
Rust standard library both have a reserve
method on strings, but in
C++ code the argument always refers to total capacity, whereas in Rust
code it always refers to additional capacity. This API on CxxString
follows the Rust convention, the same way that for the length accessor
we use the Rust conventional len()
naming and not C++ size()
or
length()
.
Panics
Panics if the new capacity overflows usize.
Appends a given string slice onto the end of this C++ string.
Trait Implementations
Either cxx::kind::Opaque
or cxx::kind::Trivial
. Read more
This method returns an ordering between self
and other
values if one exists. Read more
This method tests less than (for self
and other
) and is used by the <
operator. Read more
This method tests less than or equal to (for self
and other
) and is used by the <=
operator. Read more
This method tests greater than (for self
and other
) and is used by the >
operator. Read more