In file included from /in/interpreter.h:4:0,
                 from /in/lab4.c:1:
/in/varible.h: In function 'varkey':
/in/varible.h:50:5: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
     if (!varname[key][0])
     ^~
/in/varible.h:52:2: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
  return key;
  ^~~~~~
In file included from /in/lab4.c:1:0:
/in/interpreter.h: In function 'covexpr':
/in/interpreter.h:117:38: error: 'M_E' undeclared (first use in this function)
                     case 4: arg[tp2]=M_E; break;
                                      ^~~
/in/interpreter.h:117:38: note: each undeclared identifier is reported only once for each function it appears in