# Struct ethcore_util::nibbleslice::NibbleSlice [−] [src]

    pub struct NibbleSlice<'a> { /* fields omitted */ }

Nibble-orientated view onto byte-slice, allowing nibble-precision offsets.

This is an immutable struct. No operations actually change it.

# Example

    extern crate ethcore_util;
    use ethcore_util::nibbleslice::*;
    fn main() {
      let d1 = &[0x01u8, 0x23, 0x45];
      let d2 = &[0x34u8, 0x50, 0x12];
      let d3 = &[0x00u8, 0x12];
      let n1 = NibbleSlice::new(d1);            // 0,1,2,3,4,5
      let n2 = NibbleSlice::new(d2);            // 3,4,5,0,1,2
      let n3 = NibbleSlice::new_offset(d3, 1);  // 0,1,2
      assert!(n1 > n3);                         // 0,1,2,... > 0,1,2
      assert!(n1 < n2);                         // 0,... < 3,...
      assert!(n2.mid(3) == n3);                 // 0,1,2 == 0,1,2
      assert!(n1.starts_with(&n3));
      assert_eq!(n1.common_prefix(&n3), 3);
      assert_eq!(n2.mid(3).common_prefix(&n1), 3);
    }

## Methods

### `impl<'a, 'view> NibbleSlice<'a> where 'a: 'view`
[src]

#### `fn new(data: &'a [u8]) -> Self`

Create a new nibble slice with the given byte-slice.

#### `fn new_offset(data: &'a [u8], offset: usize) -> Self`

Create a new nibble slice with the given byte-slice with a nibble offset.

#### `fn new_composed(a: &'a NibbleSlice, b: &'a NibbleSlice) -> Self`

Create a composed nibble slice; one followed by the other.

#### `fn iter(&'a self) -> NibbleSliceIterator<'a>`

Get an iterator for the series of nibbles.

#### `fn from_encoded(data: &'a [u8]) -> (NibbleSlice, bool)`

Create a new nibble slice from the given HPE encoded data (e.g. output of `encoded()`).

#### `fn is_empty(&self) -> bool`

Is this an empty slice?

#### `fn len(&self) -> usize`

Get the length (in nibbles, naturally) of this slice.

#### `fn at(&self, i: usize) -> u8`

Get the nibble at position `i`.

#### `fn mid(&'view self, i: usize) -> NibbleSlice<'a>`

Return object which represents a view on to this slice (further) offset by `i` nibbles.

#### `fn starts_with(&self, them: &Self) -> bool`

Do we start with the same nibbles as the whole of `them`?

#### `fn common_prefix(&self, them: &Self) -> usize`

How many of the same nibbles at the beginning do we match with `them`?

#### `fn encoded(&self, is_leaf: bool) -> ElasticArray36<u8>`

Encode while nibble slice in prefixed hex notation, noting whether it `is_leaf`.

#### `fn encoded_leftmost(&self, n: usize, is_leaf: bool) -> ElasticArray36<u8>`

Encode only the leftmost `n` bytes of the nibble slice in prefixed hex notation, noting whether it `is_leaf`.

## Trait Implementations

### `impl<'a> Copy for NibbleSlice<'a>`
[src]

### `impl<'a> Clone for NibbleSlice<'a>`
[src]

#### `fn clone(&self) -> NibbleSlice<'a>`

Returns a copy of the value. Read more

#### `fn clone_from(&mut self, source: &Self)`
1.0.0

Performs copy-assignment from `source`. Read more

### `impl<'a> Eq for NibbleSlice<'a>`
[src]

### `impl<'a> Ord for NibbleSlice<'a>`
[src]

#### `fn cmp(&self, __arg_0: &NibbleSlice<'a>) -> Ordering`

This method returns an `Ordering` between `self` and `other`. Read more

### `impl<'a> PartialEq for NibbleSlice<'a>`
[src]

#### `fn eq(&self, them: &Self) -> bool`

This method tests for `self` and `other` values to be equal, and is used by `==`. Read more

#### `fn ne(&self, other: &Rhs) -> bool`
1.0.0

This method tests for `!=`.

### `impl<'a> PartialOrd for NibbleSlice<'a>`
[src]

#### `fn partial_cmp(&self, them: &Self) -> Option<Ordering>`

This method returns an ordering between `self` and `other` values if one exists. Read more

#### `fn lt(&self, other: &Rhs) -> bool`
1.0.0

This method tests less than (for `self` and `other`) and is used by the `<` operator. Read more

#### `fn le(&self, other: &Rhs) -> bool`
1.0.0

This method tests less than or equal to (for `self` and `other`) and is used by the `<=` operator. Read more

#### `fn gt(&self, other: &Rhs) -> bool`
1.0.0

This method tests greater than (for `self` and `other`) and is used by the `>` operator. Read more

#### `fn ge(&self, other: &Rhs) -> bool`
1.0.0

This method tests greater than or equal to (for `self` and `other`) and is used by the `>=` operator. Read more

### `impl<'a> Debug for NibbleSlice<'a>`
[src]

#### `fn fmt(&self, f: &mut Formatter) -> Result`

Formats the value using the given formatter.

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