197 lines
4.1 KiB
BNF
197 lines
4.1 KiB
BNF
~~~ method grammar ~~~
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<method definition> ::=
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<message pattern>
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[<temporaries> ]
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[<statements>]
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<message pattern> ::= <unary pattern> |
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<binary pattern> |
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<keyword pattern>
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<unary pattern> ::= unarySelector
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<binary pattern> ::= binarySelector <method argument>
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<keyword pattern> ::= (keyword <method argument>)+
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<temporaries> ::= '|' <temporary variable list> '|'
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<temporary variable list> ::= identifier*
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<block constructor> ::= '[' <block body> ']'
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<block body> ::= [<block argument>* '|']
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[<temporaries>] [<statements>]
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<block argument> ::= ':' identifier
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<statements> ::=
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(<return statement> ['.'] ) |
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(<expression> ['.' [<statements>]])
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<return statement> ::= returnOperator <expression>
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<expression> ::=
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<assignment> |
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<basic expression>
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<assignment> ::= <assignment target> assignmentOperator <expression>
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<basic expression> ::=
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<primary> [<messages> <cascaded messages>]
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<assignment target> := identifier
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<primary> ::=
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identifier |
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<literal> |
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<block constructor> |
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( '(' <expression> ')' )
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<messages> ::=
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(<unary message>+ <binary message>* [<keyword message>] ) |
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(<binary message>+ [<keyword message>] ) |
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<keyword message>
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<unary message> ::= unarySelector
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<binary message> ::= binarySelector <binary argument>
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<binary argument> ::= <primary> <unary message>*
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<keyword message> ::= (keyword <keyword argument> )+
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<keyword argument> ::= <primary> <unary message>* <binary message>*
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<cascaded messages> ::= (';' <messages>)*
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<literal> ::=
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<number literal> |
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<string literal> |
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<character literal> |
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<symbol literal> |
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<selector literal> |
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<array literal>
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<number literal> ::= ['-'] <number>
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<number> ::= integer | float | scaledDecimal
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<character literal> ::= quotedCharacter
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<string literal> ::= quotedString
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<symbol literal> ::= hashedString
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<selector literal> ::= quotedSelector
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<array literal> ::= '#(' <array element>* ')'
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<array element> ::= <literal> | identifier
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reserved identifiers -> nil true false self super
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~~~ lexical grammar ~~~
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character ::=
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"Any character in the implementation-defined character set"
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whitespace ::=
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"Any non-printing character interpreted as white space
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including spaces, tabs, and line breaks"
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digit ::=
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'0' | '1' | '2' | '3' | '4' | '5' | '6' | '7' | '8' | '9'
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uppercaseAlphabetic ::=
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'A' | 'B' | 'C' | 'D' | 'E' | 'F' | 'G' | 'H' | 'I' |
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'J' | 'K' | 'L' | 'M' | 'N' | 'O' | 'P' | 'Q' | 'R' |
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'S' | 'T' | 'U' | 'V' | 'W' | 'X' | 'Y' | 'Z'
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lowercaseAlphabetic ::=
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'a' | 'b' | 'c' | 'd' | 'e' | 'f' | 'g' | 'h' | 'i' |
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'j' | 'k' | 'l' | 'm' | 'n' | 'o' | 'p' | 'q' | 'r' |
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's' | 't' | 'u' | 'v' | 'w' | 'x' | 'y' | 'z'
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nonCaseLetter ::= '_'
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letter ::=
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uppercaseAlphabetic |
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lowercaseAlphabetic |
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nonCaseLetter |
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"implementation defined letters"
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commentDelimiter ::= '"'
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nonCommentDelimiter::=
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"any character that is not a commentDelimiter "
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comment :=
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commentDelimiter nonCommentDelimiter * commentDelimiter
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identifier ::= letter (letter | digit)*
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keyword ::= identifier ':'
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binaryCharacter ::=
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'!' | '%' | '&' | '*' | '+' | ',' |
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'/' | '<' | '=' | '>' | '?' | '@' |
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'\' | '~' | '|' | '-'
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binarySelector ::= binaryCharacter+
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returnOperator ::= '^'
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assignmentOperator ::= ':='
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integer ::= decimalInteger | radixInteger
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decimalInteger ::= digits
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digits ::= digit+
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radixInteger ::= radixSpecifier 'r' radixDigits
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radixSpecifier := digits
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radixDigits ::= (digit | uppercaseAlphabetic)+
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float ::= mantissa [exponentLetter exponent]
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mantissa ::= digits'.' digits
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exponent ::= ['-']decimalInteger
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exponentLetter ::= 'e' | 'd' | 'q'
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scaledDecimal ::= scaledMantissa 's' [fractionalDigits]
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scaledMantissa ::= decimalInteger | mantissa
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fractionalDigits ::= decimalInteger
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quotedCharacter ::= '$' character
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quotedString ::= stringDelimiter stringBody stringDelimiter
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stringBody ::= (nonStringDelimiter | (stringDelimiter stringDelimiter)*)
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stringDelimiter ::= ''' "a single quote"
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nonStringDelimiter ::= "any character except stringDelimiter"
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hashedString ::= '#' quotedString
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quotedSelector ::= '#' (unarySelector | binarySelector | keywordSelector)
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keywordSelector ::= keyword+
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separator ::= (whitespace | comment)*
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