ens-mode.el
ens is a key-value notation with following properties:
- no indentation-based syntax
- no implicit conversion
- no commas required when writing values
Example
title = "foo"
time = "12341234" // comment
binary-integer = 0b10101111
octal-integer = 0o81234
hex-integer = 0xdeadbeef
empty = {}
database = {
server = "192.168.11.1"
name = "install system packages"
run = [
"apt-get update"
"apt-get install -y cron foo bar"
"apt-get install hogehoge"
"rm -rf /var/lib/apt/lists/*"
]
items = [ true false false ]
ports = [
8001
8002
{ foo = "aoeu" } // heterogeneous
8003
]
empty-list = []
list-of-entities = [
{
foo = "some"
hoge = true // bool
pohe = "true" // string
}
{
pohe = "lorem ipsum"
aoeu = [ 10 20 30 40 ]
}
]
// some comment.
connection-max = 5000
real = 2.2322
}
Syntax
key ::= <symbol>
value ::= <int> | <float> | <bool> | <string> | { (key = value)* } | [ value* ]
- encoding: utf-8
- newline: \n
Semantics
*.ens is interpreted into a key-value map, as indicated in the following quasi-code:
type Map = HashMap Key MapValue
type Entity = [Pair]
type Pair = (Key, Value)
type Key = String
data Value
= ValueInt Int
| ValueFloat Double
| ValueBool Bool
| ValueString String
| ValueEntity Entity
| ValueList [Value]
data MapValue
= MapValueInt Int
| MapValueFloat Double
| MapValueBool Bool
| MapValueString String
| MapValueMap Map
| MapValueList [MapValue]
evalEntity :: Entity -> Map
evalEntity entity =
evalEntity' entity emptyMap
evalEntity' :: Entity -> Map -> Map
evalEntity' entity acc =
case entity of
[] ->
acc
(key, value) : pairList ->
evalEntity' (insert key (evalValue value) acc) pairList
evalValue :: Value -> MapValue
evalValue value =
case value of
ValueInt x ->
MapValueInt x
ValueFloat x ->
MapValueFloat x
ValueBool x ->
MapValueBool x
ValueString x ->
MapValueString x
ValueEntity x ->
MapValueMap (evalEntity x)
ValueList xs ->
MapValueList (map evalValue xs)