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Signature

pub trait ByteArrayTrait

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Trait functions

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append_word

Appends a single word of len bytes to the end of the ByteArray. This function assumes that:
  1. word could be validly converted to a bytes31 which has no more than len bytes of data.
  2. len ByteArray


### append_byte



Appends a single byte to the end of the `ByteArray`.

#### Signature

```rust
fn append_byte(ref self: ByteArray, byte: u8)

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Examples

let mut ba = "";
ba.append_byte(0);
assert!(ba == "0");

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len

Returns the length of the ByteArray.

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Signature

fn len(self: ByteArray) -> u32

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Examples

let ba: ByteArray = "byte array";
let len = ba.len();
assert!(len == 10);

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at

Returns an option of the byte at the given index of self or None if the index is out of bounds.

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Signature

fn at(self: ByteArray, index: u32) -> Option

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Examples

let ba: ByteArray = "byte array";
let byte = ba.at(0).unwrap();
assert!(byte == 98);

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rev

Returns a ByteArray with the reverse order of self.

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Signature

fn rev(self: ByteArray) -> ByteArray

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Examples

let ba: ByteArray = "123";
let rev_ba = ba.rev();
assert!(rev_ba == "321");

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append_word_rev

Appends the reverse of the given word to the end of self. This function assumes that:
  1. len < 31
  2. word is validly convertible to bytes31 of length len.

​
Signature

fn append_word_rev(ref self: ByteArray, word: felt252, len: u32)

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Examples

let mut ba: ByteArray = "";
ba.append_word_rev('123', 3);
assert!(ba == "321");