62 lines
1.1 KiB
BNF
62 lines
1.1 KiB
BNF
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<line> ::=
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<number> <statement> <EOL> | <statement> <EOL>
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<statement> ::=
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"REM" <printable-characters> |
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"PRINT" <output-list> |
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"IF" <expression> <relational-operator> <expression> "THEN" <statement> |
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"GOTO" <expression> |
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"INPUT" <variable-list> |
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"LET" <variable> "=" <expression> |
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"GOSUB" <expression> |
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"RETURN" |
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"END"
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<printable-characters> ::=
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<printable-character> | <printable-character> <printable-characters>
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<printable-character> ::=
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" " .. "~"
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<output-list> ::=
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<output-term> | <output-term> "," <output-list>
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<output-term> ::=
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<string> | <expression>
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<variable-list> ::=
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<variable> | <variable> "," <variable-list>
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<expression> ::=
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<term> |
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<expression> "+" <expression> |
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<expression> "-" <expression>
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<term> ::=
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<factor> |
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<term> "*" <term> |
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<term> "/" <term>
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factor ::=
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"-" <factor> |
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"+" <factor> |
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<variable> |
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<number> |
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"(" <expression> ")"
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<variable> ::=
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"A" .. "Z"
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<number> ::=
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<digit> | <digit> <number>
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<digit> ::=
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"0" .. "9"
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<relational-operator> ::=
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"<" | "=" | ">" | "<=" | "<>" | ">="
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<string> ::=
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'"' <printable-characters> '"'
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