Railroad Diagram Symbols
The following table describes the meaning of symbols used in railroad diagrams.
Table 3-1 Railroad Diagram Symbols
Symbol | Definition |
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Statement begins here. |
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Statement continues on next line. |
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Statement is continued from previous line. |
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Statement ends here. |
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Alternatives: optionally select one keyword. Boldface indicates default if no selection is made. |
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Alternatives: selection of one keyword is required. |
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A comma-separated list of any length is permitted. |
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Word is not further defined. Replace with value of format shown in the Terminals table. |
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Word used in statement is further defined. |
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Non-terminal used in statements is defined here. |