F♭ (pronounced F-flat) is a toy language.
Lists / Arrays are surrounded by square ([]) or round (()) brackets with optionally comma-separated elements (recall that commas are whitespace). The difference being that expressions within round brackets are executed while square brackets are lazy.
f♭> ( 1 2 )
[ [ 1 2 ] ]
f♭> ( 3, 4 )
[ [ 1 2 ] [ 3 4 ] ]
f♭> ( 5 6 * )
[ [ 1 2 ] [ 3 4 ] [ 30 ] ]
f♭> [ 1 2 * ]
[ [ 1 2 ] [ 3 4 ] [ 30 ] [ 1 2 * ] ]
Maps (aka objects or records) are surrounded by curly brackets ({}) again with optionally comma-separated elements. The key in a key value pair is actually a key as described above. Expressions within curly brackets are executed immediately.
f♭> { x: 1 y: 2 }
[ { x: 1 y: 2 } ]
f♭> { z: 3, u: 4 5 * }
[ { x: 1 y: 2 } { z: 3 u: 20 } ]
f♭> { 'v' : 3 , 'w' : 4 }
[ { x: 1 y: 2 } { z: 3 u: 20 } { v: 3 w: 4 } ]