fn matches_single_keyword(st: &SubToken) -> Option<TokenKind> {
    if let SubTokenKind::Word(w) = st.kind {
        SINGLE_KEYWORDS.get(w).cloned()
    } else {
        None
    }
}
/// Determines whether or not the given subtoken matches a single-word keyword,
/// and returns that keyword in case it does.
Determines whether or not the given subtoken matches a single-word keyword,
and returns that keyword in case it does.
Determines whether or not the given subtoken matches a single - word keyword and returns that keyword in case it does .
fn matches_single_keyword(st: &SubToken) -> Option<TokenKind> {
    if let SubTokenKind::Word(w) = st.kind {
        SINGLE_KEYWORDS.get(w).cloned()
    } else {
        None
    }
}
fn matches_single_keyword ( st : & SubToken ) -> Option < TokenKind > { if let SubTokenKind :: Word ( w ) = st . kind { SINGLE_KEYWORDS . get ( w ) . cloned ( ) } else { None } }
Determines whether or not the given subtoken matches a single-word keyword,
and returns that keyword in case it does.
Determines whether or not the given subtoken matches a single - word keyword and returns that keyword in case it does .
st
&SubToken
st
&SubToken