Grammar¶

Below is the BNF grammar for configuration files. Comments and include directives are not part of the grammar, so they are not included here. See libconfig manual at http://www.hyperrealm.com/libconfig/libconfig_manual.html#Configuration-File-Grammar for more details.

configuration = setting-list | empty
setting-list = setting | setting-list setting
setting = name (":" | "=") value (";" | "," | empty)
value = scalar-value | array | list | group
value-list = value | value-list "," value
scalar-value = boolean | integer | integer64 | hex | hex64 | float | string
scalar-value-list = scalar-value | scalar-value-list "," scalar-value
array = "[" (scalar-value-list | empty) "]"
list = "(" (value-list | empty) ")"
group = "{" (setting-list | empty) "}"
empty =

Terminals are defined below as regular expressions:

boolean

([Tt][Rr][Uu][Ee])|([Ff][Aa][Ll][Ss][Ee])

string

\"([^\"\\]|\\.)*\"

name

[A-Za-z\*][-A-Za-z0-9_\*]*

integer

[-+]?[0-9]+

integer64

[-+]?[0-9]+L(L)?

hex

0[Xx][0-9A-Fa-f]+

hex64

0[Xx][0-9A-Fa-f]+L(L)?

float

([-+]?([0-9]*)?\.[0-9]*([eE][-+]?[0-9]+)?)|
([-+]([0-9]+)(\.[0-9]*)?[eE][-+]?[0-9]+)