When, Else, and Show

Conditional branches are handled by two helpers, When (lazy) and Show (eager), with an optional .Else chain for either/or rendering.

When

func When(cond bool, fn func() View) *viewNode
func (n *viewNode) Else(fn func() View) *viewNode

When evaluates the true branch only if cond is true. Prefer it when the branch constructs anything non-trivial.

gova.When(hasError, func() gova.View {
    return gova.Text(errMsg).Color(gova.Destructive)
})

Chain .Else for an either/or:

gova.When(isDone, func() gova.View {
    return gova.Text("Done").Color(gova.Success)
}).Else(func() gova.View {
    return gova.Text("Pending").Color(gova.Secondary)
})

If the condition is false and there is no .Else, When renders an empty Group node that contributes no visible output but still occupies a slot in the parent layout for stable identity.

Show

func Show(cond bool, v any) *viewNode

Show evaluates the view eagerly; use it only when the view is cheap to construct. It is a shorthand for When(cond, func() View { return v }).

gova.Show(isLoading, gova.ProgressView())

If cond is false, Show returns an empty Group node.