private fun transform_in(v: TransformVisitor, before, begin, next, finish: AExpr, escapemark: EscapeMark)
	do
		var nexpr = n_expr

		# Shortcut on explicit range
		# Avoid the instantiation of the range and the iterator
		if self.variables.length == 1 and nexpr isa ARangeExpr and not v.phase.toolcontext.opt_no_shortcut_range.value then
			# Before: evaluate bounds
			var variable = variables.first
			before.add v.builder.make_var_assign(variable, nexpr.n_expr)
			var to = nexpr.n_expr2
			before.add to

			# Begin: check variable
			var is_ok = v.builder.make_call(v.builder.make_var_read(variable, variable.declared_type.as(not null)), method_lt.as(not null), [to.make_var_read])
			var nif = v.builder.make_if(is_ok, null)
			begin.add nif
			nif.n_else.add v.builder.make_break(escapemark)

			# Next: increment one
			var one = v.builder.make_int(1)
			var succ = v.builder.make_call(v.builder.make_var_read(variable, variable.declared_type.as(not null)), method_successor.as(not null), [one])
			next.add v.builder.make_var_assign(variable, succ)
			return
		end

		# Before: evaluate expr, make the iterator
		before.add nexpr
		var iter = v.builder.make_call(nexpr.make_var_read, method_iterator.as(not null), null)
		before.add iter

		# Begin: check iterator `is_ok`
		var is_ok = v.builder.make_call(iter.make_var_read, method_is_ok.as(not null), null)
		var nif = v.builder.make_if(is_ok, null)
		begin.add nif
		nif.n_else.add v.builder.make_break(escapemark)

		# Begin: assign automatic variables
		if variables.length == 1 then
			var item = v.builder.make_call(iter.make_var_read, method_item.as(not null), null)
			begin.add v.builder.make_var_assign(variables.first, item)
		else if variables.length == 2 then
			var key = v.builder.make_call(iter.make_var_read, method_key.as(not null), null)
			begin.add v.builder.make_var_assign(variables[0], key)
			var item = v.builder.make_call(iter.make_var_read, method_item.as(not null), null)
			begin.add v.builder.make_var_assign(variables[1], item)
		else
			abort
		end

		# Next: call next
		next.add v.builder.make_call(iter.make_var_read, method_next.as(not null), null)

		# Finish: call finish
		var method_finish = method_finish
		if method_finish != null then
			finish.add v.builder.make_call(iter.make_var_read, method_finish, null)
		end
	end