pub fn parse<'a>(buffer: &'a [u8], identifiers: &mut HashMap<usize, String>) -> Option<Token> {
    if buffer.len() == 0 {
        None
    }
    else {
        let raw = std::str::from_utf8(buffer).unwrap();
        let id: &str = &raw.to_ascii_lowercase(); // Language is case independent
        let token = match id {
            // Noun keywords
            "all" => Token::Noun(Noun::All),
            "empty" => Token::Noun(Noun::Empty),
            "level" => Token::Noun(Noun::Level),
            "image" => Token::Noun(Noun::Image),
            // Verb keywords
            "eat" => Token::Verb(Verb::Eat),
            "fear" => Token::Verb(Verb::Fear),
            "follow" => Token::Verb(Verb::Follow),
            "has" => Token::Verb(Verb::Has),
            "is" => Token::Verb(Verb::Is),
            "make" => Token::Verb(Verb::Make),
            "mimic" => Token::Verb(Verb::Mimic),
            "play" => Token::Verb(Verb::Play),
            // Property keywords
            // - Initializers
            "you" => Token::Property(Property::You),
            "you2" => Token::Property(Property::You2),
            "group" => Token::Property(Property::Group),
            "tele" => Token::Property(Property::Tele),
            // - Static
            "float" => Token::Property(Property::Float),
            // - I/O
            "text" => Token::Property(Property::Text),
            "word" => Token::Property(Property::Word),
            // - Program
            "win" => Token::Property(Property::Win),
            "defeat" => Token::Property(Property::Defeat),
            "sleep" => Token::Property(Property::Sleep),
            // - Other
            "done" => Token::Property(Property::Done),
            // - You
            "move" => Token::Property(Property::Move),
            "turn" => Token::Property(Property::Turn),
            "fall" => Token::Property(Property::Fall),
            "more" => Token::Property(Property::More),
            "right" => Token::Property(Property::Right),
            "up" => Token::Property(Property::Up),
            "left" => Token::Property(Property::Left),
            "down" => Token::Property(Property::Down),
            "chill" => Token::Property(Property::Chill),
            // - Group
            "shift" => Token::Property(Property::Shift),
            "sink" => Token::Property(Property::Sink),
            "swap" => Token::Property(Property::Swap),
            // - Level
            "power" => Token::Property(Property::Power),
            // Prefix keywords 
            "idle" => Token::Prefix(Prefix::Idle),
            "lonely" => Token::Prefix(Prefix::Lonely),
            "often" => Token::Prefix(Prefix::Often),
            "seldom" => Token::Prefix(Prefix::Seldom),
            // "And"
            "and" => Token::And,
            // "Not"
            "not" => Token::Not,
            // "Conditional" keywords
            "facing" => Token::Conditional(Conditional::Facing),
            "near" => Token::Conditional(Conditional::Near),
            "on" => Token::Conditional(Conditional::On),
            "without" => Token::Conditional(Conditional::Without),
            // Everything else (identifiers)
            _ => {
                let mut unique = true;
                let mut existing_id = 0;
                for (value, identifier) in identifiers.iter() {
                    if &id == &identifier {
                        existing_id = *value;
                        unique = false;
                        break;
                    }
                }
                if unique {
                    let new_id = identifiers.len();
                    // For new strings, the unique identifier is just the length 
                    // of the set, i.e. each identifier is one grer than the previous.
                    identifiers.insert(new_id, id.to_string());
                    Token::Noun(Noun::Identifier(new_id))
                }
                else {
                    Token::Noun(Noun::Identifier(existing_id))
                }
            }
        };
        Some(token)
    }
}
/// Parses a char slice into the associated token. Returns None if the slice is empty.
/// If the token is a newly seen identifier, associates the identifier with an integer
/// in the HashMap provided.
/// 
/// # Arguments
/// 
/// * `buffer` - A character slice to parse the token from.
/// 
/// * `identifiers` - A HashMap that associates each unique token identifer to an usize.
Parses a char slice into the associated token. Returns None if the slice is empty.
If the token is a newly seen identifier, associates the identifier with an integer
in the HashMap provided.
Parses a char slice into the associated token . Returns None if the slice is empty . If the token is a newly seen identifier associates the identifier with an integer in the HashMap provided .
pub fn parse<'a>(buffer: &'a [u8], identifiers: &mut HashMap<usize, String>) -> Option<Token> {
    if buffer.len() == 0 {
        None
    }
    else {
        let raw = std::str::from_utf8(buffer).unwrap();
        let id: &str = &raw.to_ascii_lowercase(); // Language is case independent
        let token = match id {
            // Noun keywords
            "all" => Token::Noun(Noun::All),
            "empty" => Token::Noun(Noun::Empty),
            "level" => Token::Noun(Noun::Level),
            "image" => Token::Noun(Noun::Image),
            // Verb keywords
            "eat" => Token::Verb(Verb::Eat),
            "fear" => Token::Verb(Verb::Fear),
            "follow" => Token::Verb(Verb::Follow),
            "has" => Token::Verb(Verb::Has),
            "is" => Token::Verb(Verb::Is),
            "make" => Token::Verb(Verb::Make),
            "mimic" => Token::Verb(Verb::Mimic),
            "play" => Token::Verb(Verb::Play),
            // Property keywords
            // - Initializers
            "you" => Token::Property(Property::You),
            "you2" => Token::Property(Property::You2),
            "group" => Token::Property(Property::Group),
            "tele" => Token::Property(Property::Tele),
            // - Static
            "float" => Token::Property(Property::Float),
            // - I/O
            "text" => Token::Property(Property::Text),
            "word" => Token::Property(Property::Word),
            // - Program
            "win" => Token::Property(Property::Win),
            "defeat" => Token::Property(Property::Defeat),
            "sleep" => Token::Property(Property::Sleep),
            // - Other
            "done" => Token::Property(Property::Done),
            // - You
            "move" => Token::Property(Property::Move),
            "turn" => Token::Property(Property::Turn),
            "fall" => Token::Property(Property::Fall),
            "more" => Token::Property(Property::More),
            "right" => Token::Property(Property::Right),
            "up" => Token::Property(Property::Up),
            "left" => Token::Property(Property::Left),
            "down" => Token::Property(Property::Down),
            "chill" => Token::Property(Property::Chill),
            // - Group
            "shift" => Token::Property(Property::Shift),
            "sink" => Token::Property(Property::Sink),
            "swap" => Token::Property(Property::Swap),
            // - Level
            "power" => Token::Property(Property::Power),
            // Prefix keywords 
            "idle" => Token::Prefix(Prefix::Idle),
            "lonely" => Token::Prefix(Prefix::Lonely),
            "often" => Token::Prefix(Prefix::Often),
            "seldom" => Token::Prefix(Prefix::Seldom),
            // "And"
            "and" => Token::And,
            // "Not"
            "not" => Token::Not,
            // "Conditional" keywords
            "facing" => Token::Conditional(Conditional::Facing),
            "near" => Token::Conditional(Conditional::Near),
            "on" => Token::Conditional(Conditional::On),
            "without" => Token::Conditional(Conditional::Without),
            // Everything else (identifiers)
            _ => {
                let mut unique = true;
                let mut existing_id = 0;
                for (value, identifier) in identifiers.iter() {
                    if &id == &identifier {
                        existing_id = *value;
                        unique = false;
                        break;
                    }
                }
                if unique {
                    let new_id = identifiers.len();
                    // For new strings, the unique identifier is just the length 
                    // of the set, i.e. each identifier is one grer than the previous.
                    identifiers.insert(new_id, id.to_string());
                    Token::Noun(Noun::Identifier(new_id))
                }
                else {
                    Token::Noun(Noun::Identifier(existing_id))
                }
            }
        };
        Some(token)
    }
}
pub fn parse < ' a > ( buffer : & ' a [ u8 ] , identifiers : & mut HashMap < usize , String > ) -> Option < Token > { if buffer . len ( ) == 0 { None } else { let raw = std :: str :: from_utf8 ( buffer ) . unwrap ( ) ; let id : & str = & raw . to_ascii_lowercase ( ) ; // Language is case independent let token = match id { // Noun keywords " " => Token :: Noun ( Noun :: All ) , " " => Token :: Noun ( Noun :: Empty ) , " " => Token :: Noun ( Noun :: Level ) , " " => Token :: Noun ( Noun :: Image ) , // Verb keywords " " => Token :: Verb ( Verb :: Eat ) , " " => Token :: Verb ( Verb :: Fear ) , " " => Token :: Verb ( Verb :: Follow ) , " " => Token :: Verb ( Verb :: Has ) , " " => Token :: Verb ( Verb :: Is ) , " " => Token :: Verb ( Verb :: Make ) , " " => Token :: Verb ( Verb :: Mimic ) , " " => Token :: Verb ( Verb :: Play ) , // Property keywords // - Initializers " " => Token :: Property ( Property :: You ) , " " => Token :: Property ( Property :: You2 ) , " " => Token :: Property ( Property :: Group ) , " " => Token :: Property ( Property :: Tele ) , // - Static " " => Token :: Property ( Property :: Float ) , // - I/O " " => Token :: Property ( Property :: Text ) , " " => Token :: Property ( Property :: Word ) , // - Program " " => Token :: Property ( Property :: Win ) , " " => Token :: Property ( Property :: Defeat ) , " " => Token :: Property ( Property :: Sleep ) , // - Other " " => Token :: Property ( Property :: Done ) , // - You " " => Token :: Property ( Property :: Move ) , " " => Token :: Property ( Property :: Turn ) , " " => Token :: Property ( Property :: Fall ) , " " => Token :: Property ( Property :: More ) , " " => Token :: Property ( Property :: Right ) , " " => Token :: Property ( Property :: Up ) , " " => Token :: Property ( Property :: Left ) , " " => Token :: Property ( Property :: Down ) , " " => Token :: Property ( Property :: Chill ) , // - Group " " => Token :: Property ( Property :: Shift ) , " " => Token :: Property ( Property :: Sink ) , " " => Token :: Property ( Property :: Swap ) , // - Level " " => Token :: Property ( Property :: Power ) , // Prefix keywords  " " => Token :: Prefix ( Prefix :: Idle ) , " " => Token :: Prefix ( Prefix :: Lonely ) , " " => Token :: Prefix ( Prefix :: Often ) , " " => Token :: Prefix ( Prefix :: Seldom ) , // "And" " " => Token :: And , // "Not" " " => Token :: Not , // "Conditional" keywords " " => Token :: Conditional ( Conditional :: Facing ) , " " => Token :: Conditional ( Conditional :: Near ) , " " => Token :: Conditional ( Conditional :: On ) , " " => Token :: Conditional ( Conditional :: Without ) , // Everything else (identifiers) _ => { let mut unique = true ; let mut existing_id = 0 ; for ( value , identifier ) in identifiers . iter ( ) { if & id == & identifier { existing_id = * value ; unique = false ; break ; } } if unique { let new_id = identifiers . len ( ) ; // For new strings, the unique identifier is just the length  // of the set, i.e. each identifier is one grer than the previous. identifiers . insert ( new_id , id . to_string ( ) ) ; Token :: Noun ( Noun :: Identifier ( new_id ) ) } else { Token :: Noun ( Noun :: Identifier ( existing_id ) ) } } } ; Some ( token ) } }
Parses a char slice into the associated token.
Parses a char slice into the associated token .
buffer
&'a [u8]
identifiers
&mut HashMap<usize, String>
buffer
&'a [u8]
identifiers
&mut HashMap<usize, String>