A short summary of the elements used in syntax diagrams.
| Syntax symbol | Description | |
|---|---|---|
| := | production rule ("non-terminal can be expanded to ...") | |
| { ... } | 0..N occurrences ("*") | |
| [ ... ] | 0..1 occurrences ("?") | |
| ( ... ) | grouping | |
| ... ** | ** ... | alternative |
| ' ... ' | literal | |
| ( ... ) | placeholder for literal | |
| ? ... ? | comment |