1 Grammar of the schema language {#flatbuffers_grammar} 2 ============================== 3 4 schema = include* 5 ( namespace\_decl | type\_decl | enum\_decl | root\_decl | 6 file_extension_decl | file_identifier_decl | 7 attribute\_decl | object )* 8 9 include = `include` string\_constant `;` 10 11 namespace\_decl = `namespace` ident ( `.` ident )* `;` 12 13 attribute\_decl = `attribute` string\_constant `;` 14 15 type\_decl = ( `table` | `struct` ) ident metadata `{` field\_decl+ `}` 16 17 enum\_decl = ( `enum` | `union` ) ident [ `:` type ] metadata `{` commasep( 18 enumval\_decl ) `}` 19 20 root\_decl = `root_type` ident `;` 21 22 field\_decl = ident `:` type [ `=` scalar ] metadata `;` 23 24 type = `bool` | `byte` | `ubyte` | `short` | `ushort` | `int` | `uint` | 25 `float` | `long` | `ulong` | `double` 26 | `string` | `[` type `]` | ident 27 28 enumval\_decl = ident [ `=` integer\_constant ] 29 30 metadata = [ `(` commasep( ident [ `:` single\_value ] ) `)` ] 31 32 scalar = integer\_constant | float\_constant 33 34 object = { commasep( ident `:` value ) } 35 36 single\_value = scalar | string\_constant 37 38 value = single\_value | object | `[` commasep( value ) `]` 39 40 commasep(x) = [ x ( `,` x )\* ] 41 42 file_extension_decl = `file_extension` string\_constant `;` 43 44 file_identifier_decl = `file_identifier` string\_constant `;` 45 46 integer\_constant = -?[0-9]+ | `true` | `false` 47 48 float\_constant = -?[0-9]+.[0-9]+((e|E)(+|-)?[0-9]+)? 49
