Assign to this string the value of the specified replacement string, propagate to this object the allocator of replacement if the ALLOCATOR type has trait propagate_on_container_copy_assignment, and return a reference providing modifiable access to this string. Note that this method has exactly the same behavior as the corresponding operator=.
Declared in <bslstl_string.h>
basic_string<char32_t>&
assign(basic_string<char32_t> const& replacement);