sample_trie_e_access_traits Interface

# `sample_trie_e_access_traits` Interface

A sample trie element-access traits.

This class serves to show the interface an element- access traits class needs to support.

Defined in: `sample_trie_e_access_traits.hpp`

## Public Types and Constants

### General definitions.

Type | Definition | Description
    size_type
    size_t, e.g.
| Size type.
    key_type
    std::string, e.g.
| Key type.
    const_key_reference
    const string &, e.g.
| Const key reference type.

### Element definitions.

Type | Definition | Description
    const_iterator
    string::const_iterator, e.g.
| Element `const` iterator type.
    e_type
    char, e.g.
| Element type.
    max_size
    4, e.g.
| Number of distinct elements.

## Public Methods

### Access methods.

Method | Description
    inline static const_iterator
      begin
      (const_key_reference r_key)
| Returns a `const_iterator` to the first element of `r_key`.
    inline static const_iterator
      end
      (const_key_reference r_key)
| Returns a `const_iterator` to the after-last element of `r_key`.
    inline static size_type
      e_pos
      (e_type e)
| Maps an `element` to a position.