3027. [networking.ts] DynamicBuffer prepare exception specification

Section: 16.2.4 [networking.ts::buffer.reqmts.dynamicbuffer] Status: New Submitter: Vinnie Falco Opened: 2017-10-16 Last modified: 2020-09-06

Priority: 3

View other active issues in [networking.ts::buffer.reqmts.dynamicbuffer].

View all other issues in [networking.ts::buffer.reqmts.dynamicbuffer].

View all issues with New status.

Discussion:

Addresses: networking.ts

The current wording for the DynamicBuffer prepare member function implies that std::length_error is the only allowable thrown exception. This should be changed to reflect that any exception may be thrown, with std::length_error thrown in particular when size() + n exceeds max_size().

[2017-11-08]

Priority set to 3 after five votes on mailing list

Proposed resolution:

This wording is relative to N4588.

  1. Change 16.2.4 [networking.ts::buffer.reqmts.dynamicbuffer], Table 14 "DynamicBuffer requirements", as indicated:

    Table 14 — DynamicBuffer requirements
    expression return type assertion/note pre/post-condition
    […]
    x.prepare(n) X::mutable_buffers_type Returns a mutable buffer sequence u
    representing the writable bytes, and where
    buffer_size(u) == n . The dynamic buffer
    reallocates memory as required. All constant or
    mutable buffer sequences previously obtained using
    data() or prepare() are invalidated.
    Throws: length_error if size() + n
    exceeds max_size() or any other exception
    if the request cannot otherwise be satisfied    .