fn index_if_ok(&self, vaddr: usize) -> Option<usize> {
        if self.kind.vaddr_ok(vaddr) {
            Some(vaddr.pml4_index())
        } else {
            None
        }
    }
/// Returns the PML4 index for the given virtual address if and only if the
/// address is canonical and within the allowed range for this PML4.
Returns the PML4 index for the given virtual address if and only if the
address is canonical and within the allowed range for this PML4.
Returns the PML4 index for the given virtual address if and only if the address is canonical and within the allowed range for this PML4 .
fn index_if_ok(&self, vaddr: usize) -> Option<usize> {
        if self.kind.vaddr_ok(vaddr) {
            Some(vaddr.pml4_index())
        } else {
            None
        }
    }
fn index_if_ok ( & self , vaddr : usize ) -> Option < usize > { if self . kind . vaddr_ok ( vaddr ) { Some ( vaddr . pml4_index ( ) ) } else { None } }
Returns the PML4 index for the given virtual address if and only if the
address is canonical and within the allowed range for this PML4.
Returns the PML4 index for the given virtual address if and only if the address is canonical and within the allowed range for this PML4 .
&self
vaddr
usize