---
name: Digest::MD5
runtime: pp
source: src/native/Digest/MD5/pp.rs
---
```{index} single: Digest::MD5; Perl module (pp runtime)
```

# Digest::MD5

Native implementation of Digest::MD5

Provides MD5 hashing functionality compatible with the Digest::MD5 Perl module.

# Synopsis

    use Digest::MD5 qw(md5_hex md5_base64);

    my $hex    = md5_hex("some data");
    my $base64 = md5_base64("some data");

    # OO interface for incremental hashing
    my $ctx = Digest::MD5->new;
    $ctx->add("first chunk");
    $ctx->add("second chunk");
    my $digest = $ctx->hexdigest;

# Functional Interface

- `md5($data)` - Returns binary MD5 digest (16 bytes)
- `md5_hex($data)` - Returns hexadecimal MD5 digest (32 characters)
- `md5_base64($data)` - Returns base64-encoded MD5 digest (22 characters, no padding)

# Object-Oriented Interface

- `Digest::MD5->new()` - Creates a new MD5 context object
- `$ctx->add($data, ...)` - Adds data to the context
- `$ctx->addfile($fh)` - Adds data from a filehandle (not yet implemented)
- `$ctx->digest()` - Returns binary digest and resets the context
- `$ctx->hexdigest()` - Returns hex digest and resets the context
- `$ctx->b64digest()` - Returns base64 digest (no padding) and resets the context
- `$ctx->reset()` - Resets the context
- `$ctx->clone()` - Clones the context

# Implementation Notes

The OO interface stores accumulated data in a blessed hash reference.
The hash uses a special key `_data` to store the accumulated bytes.
Computing the actual MD5 hash is done when `digest()`, `hexdigest()`, or
`b64digest()` is called.

This approach avoids the complexity of storing Rust state (Md5 hasher)
in Perl values while maintaining compatibility with the Perl interface.