English
The map that converts an OrderEmbedding to one that preserves < is defined; it yields a RelEmbedding that preserves LT.
Русский
Переобразование вложения в вложение, сохраняющее <, задаёт RelEmbedding, сохраняющее LT.
LaTeX
$$$\\operatorname{ltEmbedding} : (\\alpha \\too \\beta) \\to_r ( (\\cdot < \\cdot) : \\alpha \\to \\alpha \\to \\mathrm{Prop} ) \\hookrightarrow_r ( (\\cdot < \\cdot) : \\beta \\to \\beta \\to \\mathrm{Prop} ).$$$
Lean4
/-- `<` is preserved by order embeddings of preorders. -/
def ltEmbedding : ((· < ·) : α → α → Prop) ↪r ((· < ·) : β → β → Prop) :=
{ f with map_rel_iff' := by simp [lt_iff_le_not_ge, f.map_rel_iff] }