grammar PIL::Native::Syntax;

rule literal {
    nil | true | false | <pointySub>
    | <stringLiteral>  | <singleQuoteStringLiteral>
    | <naturalOrFloat> | <integer>
}

rule stringLiteral              { " <-['"]>+ " }
rule singleQuoteStringLiteral   { ' <-[']> ' }
rule naturalOrFloat             { <integer> | <integer>.<integer> }
rule integer                    { \d+ }

rule identifier         { <[$@%&:]> <-[ \n\t.`!,;()[\]{}<>#]>* }
rule method             { <-[ \n\t()0123456789.`!]> <-[ \n\t();,.`!]>* }
    
rule pointySub          { -\> <pointySubParams> <pointySubBody> }
rule pointySubParams    { <identifierCommaList>? }
rule pointySubBody      { \{ <expressionList> \} }
    
rule expressionList     { <expression> [; <expressionList> | ;? ] }
rule expression         { <expressionStmt> <call>? }
rule expressionStmt     {
    \( <expression> \)
    | <selfExpression> | <arrayExpression> | <hashExpression>
    | <literal> | <variableExpression>
}
    
rule call           { <[`.!]> <methodCall> }
rule methodCall     { <method> <argList>? }
rule argList        { \( <expressionCommaList>? \) }

rule selfExpression     { self }
rule variableExpression { <identifier> }
rule arrayExpression    { \[ <expressionCommaList> \] }
rule hashExpression     { \{ <pairExpressionCommaList> \} }
rule pairExpression     { <expression> =\> <expression> }
   
rule expressionCommaList        { <expression> [ , <expressionCommaList> ]? }
rule identifierCommaList        { <identifier> [ , <identifierCommaList> ]? }
rule pairExpressionCommaList    { <pairExpression> [ , <pairExpressionCommaList> ]? }