using std a posteriori does not fix endl lookup

[nthiery]

If one forgets to "use std" before accessing "endl", then "using namespace std" a posteriori does not resolve the lookup:

In[1] cout << 1 << endl;

input_line_7:2:2: error: use of undeclared identifier 'cout'; did you mean 'std::cout'?
 cout << 1 << endl;
 ^~~~
...

All good for now.

In[2] using namespace std;

One would now expect the following to work, but it does not:

In[3] cout << 1 << endl;

input_line_9:2:15: error: reference to overloaded function could not be resolved; did you mean to call it?
 cout << 1 << endl;
              ^~~~
...

Full transcript in test-namespace-endl.pdf

[gouarin]

It's a cling issue. I will test on the last version of cling to be sure that this issue was not already solved.

[SylvainCorlay]

cc @vgvassilev this is an upstream issue apparently. Might be solved in 0.4

[nthiery]

For the record: the issue is still there with cling 0.5:

clangdev                  5.0.0                   cling_1  [cling]  gouarin
cling                     0.5                           3  [cling]  gouarin
cling-patches             1                             0    QuantStack
clingkernel               0.0.2                     <pip>
cppzmq                    4.2.2                   cling_0  [cling]  gouarin
llvmdev                   5.0.0                   cling_1  [cling]  gouarin
xeus-cling                0.0.10                        0    gouarin
zeromq                    4.2.3                   cling_3  [cling]  gouarin

[ghost]

the issue is still there with cling 0.7 and xeus-cling 0.10