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diff --git a/docs/chapter17b/17-grammar.md b/docs/chapter17b/17-grammar.md new file mode 100644 index 00000000..88f6fc93 --- /dev/null +++ b/docs/chapter17b/17-grammar.md @@ -0,0 +1,123 @@ +# Grammar for Chapter 17b + +English | [日本語](17-grammar.ja.md) + +```antlrv4 +grammar SimpleLanguage; + +// Name lookup, assignable operands, type compatibility, and access permissions +// are checked by the compiler in addition to these syntax rules. +program : statement* EOF ; + +block : '{' statement* '}' ; + +statement + : block + | returnStatement + | ifStatement + | whileStatement + | forStatement + | breakStatement + | continueStatement + | structDeclaration + | declaration ';' + | assignment ';' + | ';' + ; + +returnStatement : 'return' assignment ';' ; +ifStatement : 'if' '(' assignment ')' statement ('else' statement)? ; +whileStatement : 'while' '(' assignment ')' statement ; +breakStatement : 'break' ';' ; +continueStatement : 'continue' ';' ; + +forStatement + : 'for' '(' (declaration | assignment)? ';' assignment? ';' assignment? ')' statement + ; + +structDeclaration : 'struct' IDENTIFIER block ';' ; + +declaration : declarationType binding (',' binding)* ; +declarationType : type | 'var' | 'val' ; +binding : bindingModifier? IDENTIFIER ('=' initializer)? ; +bindingModifier : '!' | '~' ; +initializer : assignment ; + +// The prefix qualifies the named struct reference, not an enclosing array. +// Each [] / [~] suffix qualifies its own array layer. ? requires a reference. +type + : primitiveType typeSuffix* + | accessModifier? typeName typeSuffix* + ; +accessModifier : '!' | '~' ; +typeSuffix : '?' | '[]' | '[~]' ; +typeName : IDENTIFIER ; + +primitiveType + : 'int' | 'i8' | 'i16' | 'i32' | 'i64' + | 'u1' | 'u8' | 'u16' | 'u32' | 'byte' | 'bool' + | 'flt' | 'f32' | 'f64' + ; + +assignment : expression (assignmentOperator assignment)? ; +assignmentOperator + : '=' | '+=' | '-=' | '*=' | '/=' | '&=' | '|=' | '^=' + | '<<=' | '>>=' | '>>>=' + ; + +expression : bitwiseExpression ('?' assignment (':' assignment)?)? ; + +bitwiseExpression + : comparisonExpression (('&' | '|' | '^') comparisonExpression)* + ; + +comparisonExpression + : shiftExpression (('==' | '!=' | '<' | '<=' | '>' | '>=') shiftExpression)* + ; + +shiftExpression + : additiveExpression (('<<' | '>>' | '>>>') additiveExpression)* + ; + +additiveExpression + : multiplicativeExpression (('+' | '-') multiplicativeExpression)* + ; + +multiplicativeExpression + : unaryExpression (('*' | '/') unaryExpression)* + ; + +unaryExpression + : ('-' | '!') unaryExpression + | updateOperator IDENTIFIER + | postfixExpression + ; + +// Prefix updates require a local name; postfix updates also allow fields +// and array elements. All updates require an assignable operand. +updateOperator : '++' | '--' ; +postfixExpression : primaryExpression postfixSuffix* updateOperator? ; +postfixSuffix : '.' IDENTIFIER | '[' assignment ']' | '#' ; + +primaryExpression + : INTEGER_LITERAL + | FLOAT_LITERAL + | 'true' + | 'false' + | 'null' + | IDENTIFIER + | '(' assignment ')' + | newExpression + ; + +// Struct initialization uses a block; array allocation supplies a length. +newExpression : 'new' type ('[' assignment ']' | block)? ; + +INTEGER_LITERAL : '0' | [1-9] DIGIT* ; +FLOAT_LITERAL : DIGIT+ ('.' DIGIT* ('e' DIGIT+)? | 'e' DIGIT+) ; +IDENTIFIER : NON_DIGIT (NON_DIGIT | DIGIT)* ; +fragment NON_DIGIT : [a-zA-Z_] ; +fragment DIGIT : [0-9] ; +WHITESPACE : [ \t\r\n]+ -> skip ; +LINE_COMMENT : '//' ~[\r\n]* -> skip ; +``` |
