-redef class AAtArg
- # Get `self` as a `String`.
- # Return null if not a string.
- fun as_string: nullable String
- do
- if not self isa AExprAtArg then return null
- var nexpr = n_expr
- if not nexpr isa AStringFormExpr then return null
- return nexpr.value.as(not null)
- end
-
- # Get `self` as an `Int`.
- # Return null if not an integer.
- fun as_int: nullable Int
- do
- if not self isa AExprAtArg then return null
- var nexpr = n_expr
- if not nexpr isa AIntExpr then return null
- return nexpr.value.as(not null)
- end
-
- # Get `self` as a single identifier.
- # Return null if not a single identifier.
- fun as_id: nullable String
- do
- if not self isa AExprAtArg then return null
- var nexpr = n_expr
- if not nexpr isa ACallExpr then return null
- if not nexpr.n_expr isa AImplicitSelfExpr then return null
- if not nexpr.n_args.n_exprs.is_empty then return null
- return nexpr.n_id.text
- end
-end
-