menu_book Course Curriculum (Nim) expand_more
variants
Learn variants in Nim with a construct-specific explanation, unique example, engineering boundary, and mastery check.
variants is a focused Nim topic inside Types. This lesson explains the construct itself, the state or value it operates on, and the observable result it produces.
Read the example as a small executable experiment. Identify the exact syntax that belongs to variants, then change one input and predict the result before running it.
Topic-specific example
type ValueKind=enum vkInt,vkText
type Value=object
case kind:ValueKind
of vkInt: i:int
of vkText: s:string
variants has rules that are easy to miss when the example is copied mechanically. Check the feature-specific boundary shown by this construct: scope, mutability, evaluation order, type constraints, lifetime, error behavior, compile-time restrictions, or resource cleanup where applicable.