Cannot get node/token name

[tyru]

vimlparser should provide node/token map of s:NODE_* and s:TOKEN_* constants?

[tyru]

I want to write like this.

  if a:node.type !=# s:NODE_STRING
    throw s:Err(printf('expected regexp string node, but got %s node', s:node_name[a:node.type]), a:node.pos)
  endif

and maybe vimlparser users sometimes needs this assertion.

@blueyed what do you think? vint does not need this type assertion? or already implemented in vint?