English
This construction equips a completely metrizable space with a complete metric. It can be used to obtain a canonical upgraded metrizable structure.
Русский
Данная конструкция наделяет полностью метризуемое пространство полной метрикой, образуя каноническую обновлённую метрическую структуру.
LaTeX
$$$\\text{upgradeIsCompletelyMetrizable}(X)\\text{ yields an } UpgradedIsCompletelyMetrizableSpace X\\text{ with a distinguished complete metric.}$$$
Lean4
/-- This definition endows a completely metrizable space with a complete metric. Use it as:
`letI := upgradeIsCompletelyMetrizable X`. -/
noncomputable def upgradeIsCompletelyMetrizable (X : Type*) [TopologicalSpace X] [IsCompletelyMetrizableSpace X] :
UpgradedIsCompletelyMetrizableSpace X :=
letI := completelyMetrizableMetric X
{ complete_completelyMetrizableMetric X with }