How to convert a letter character into the corresponding escaped special character

Question

I need a function that would give me the escaped special character from the letter character. It would apply only when it makes sense: 't', 'n', 'r', 'b', 'f', 'v'.

Right now, here is my implementation:

typedef struct SpecialCharacter
{
    SpecialCharacter( char letter, char special )
    {
        m_letter = letter;
        m_special = special;
    }

    char m_letter;
    char m_special;
} SpecialCharacter;

typedef std::vector<SpecialCharacter> SpecialCharacters;

static const SpecialCharacters& GetSpecialCharacters()
{
    static SpecialCharacters characters;
    if ( characters.empty() )
    {
        characters.push_back( SpecialCharacter( 'b', '\b' ) );
        characters.push_back( SpecialCharacter( 'f', '\f' ) );
        characters.push_back( SpecialCharacter( 'n', '\n' ) );
        characters.push_back( SpecialCharacter( 'r', '\r' ) );
        characters.push_back( SpecialCharacter( 't', '\t' ) );
        characters.push_back( SpecialCharacter( 'v', '\v' ) );
    }
    return characters;
}

static bool getEscaped( char letter, char& escaped )
{
    for ( SpecialCharacters::const_iterator iter = GetSpecialCharacters().begin();
          iter != GetSpecialCharacters().end();
          ++iter )
    {
        if ( letter == iter->m_letter)
        {
            escaped = iter->m_special;
            return true;
        }
    }
    return false;
}

I don't like the way I'm adding elements to the characters vector:

characters.push_back( SpecialCharacter( 'b', '\b' ) );

Would there be a way to do:

characters.push_back( SpecialCharacter( 'b' ) );

and then have something like:

SpecialCharacter( char letter )
{
    m_letter = letter;
    m_special = '\' + letter; // does not work, of course!
}

I'd like a way to merge '\' and 'n' into '\n', or get '\n' from 'n' by any different way...

Edit: case statement is what I had originally before I moved the code to a vector of struct (because I need a function to do the way around). So that would not be a good solution to my problem. I'd like to transform 'n' to '\n' without any kind of "lookup table"

Answer 1

n and \n are completely different characters. They are not related to each other in any way. \n is just a mnemonic. There is no formula.