This page is a snapshot from the LWG issues list, see the Library Active Issues List for more information and the meaning of NAD status.

### 73. `is_open` should be const

Section: 29.10 [file.streams] Status: NAD Submitter: Matt Austern Opened: 1998-08-27 Last modified: 2017-06-15

Priority: Not Prioritized

View all other issues in [file.streams].

View all issues with NAD status.

Discussion:

Classes `basic_ifstream`, `basic_ofstream`, and `basic_fstream` all have a member function `is_open`. It should be a `const` member function, since it does nothing but call one of `basic_filebuf`'s const member functions.

Rationale:

Not a defect. This is a deliberate feature; const streams would be meaningless.