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74 lines
2.1 KiB
Markdown
74 lines
2.1 KiB
Markdown
## EBNF
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```ebnf
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schema = include* ( namespace_decl | type_decl | enum_decl | root_decl |
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file_extension_decl | file_identifier_decl |
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attribute_decl | rpc_decl | object )*
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include = `include` string_constant `;`
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namespace_decl = `namespace` ident ( `.` ident )* `;`
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attribute_decl = `attribute` ident | `"` ident `"` `;`
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type_decl = ( `table` | `struct` ) ident metadata `{` field_decl+ `}`
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enum_decl = ( `enum` ident `:` type | `union` ident ) metadata `{`
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commasep( enumval_decl ) `}`
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root_decl = `root_type` ident `;`
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field_decl = ident `:` type [ `=` scalar ] metadata `;`
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rpc_decl = `rpc_service` ident `{` rpc_method+ `}`
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rpc_method = ident `(` ident `)` `:` ident metadata `;`
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type = `bool` | `byte` | `ubyte` | `short` | `ushort` | `int` | `uint` |
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`float` | `long` | `ulong` | `double` | `int8` | `uint8` | `int16` |
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`uint16` | `int32` | `uint32`| `int64` | `uint64` | `float32` |
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`float64` | `string` | `[` type `]` | ident
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enumval_decl = ident [ `=` integer_constant ] metadata
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metadata = [ `(` commasep( ident [ `:` single_value ] ) `)` ]
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scalar = boolean_constant | integer_constant | float_constant
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object = `{` commasep( ident `:` value ) `}`
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single_value = scalar | string_constant
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value = single_value | object | `[` commasep( value ) `]`
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commasep(x) = [ x ( `,` x )\* ]
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file_extension_decl = `file_extension` string_constant `;`
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file_identifier_decl = `file_identifier` string_constant `;`
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string_constant = `\".*?\"`
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ident = `[a-zA-Z_][a-zA-Z0-9_]*`
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`[:digit:]` = `[0-9]`
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`[:xdigit:]` = `[0-9a-fA-F]`
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dec_integer_constant = `[-+]?[:digit:]+`
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hex_integer_constant = `[-+]?0[xX][:xdigit:]+`
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integer_constant = dec_integer_constant | hex_integer_constant
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dec_float_constant = `[-+]?(([.][:digit:]+)|([:digit:]+[.][:digit:]*)|([:digit:]+))([eE][-+]?[:digit:]+)?`
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hex_float_constant = `[-+]?0[xX](([.][:xdigit:]+)|([:xdigit:]+[.][:xdigit:]*)|([:xdigit:]+))([pP][-+]?[:digit:]+)`
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special_float_constant = `[-+]?(nan|inf|infinity)`
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float_constant = dec_float_constant | hex_float_constant | special_float_constant
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boolean_constant = `true` | `false`
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```
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