Lookup rules for template parameters

A parameter p in a template is even substituted in the expression x.p. Thus, template arguments can be used as field names and a global symbol can be shadowed by the same argument name even when fully qualified:

  1. # module 'm'
  3. type
  4.   Lev = enum
  5.     levA, levB
  7. var abclev = levB
  9. template tstLev(abclev: Lev) =
  10.   echo abclev, " ", m.abclev
  12. tstLev(levA)
  13. # produces: 'levA levA'

But the global symbol can properly be captured by a bind statement:

  1. # module 'm'
  3. type
  4.   Lev = enum
  5.     levA, levB
  7. var abclev = levB
  9. template tstLev(abclev: Lev) =
  10.   bind m.abclev
  11.   echo abclev, " ", m.abclev
  13. tstLev(levA)
  14. # produces: 'levA levB'