Just like in Lua, you can build modules using tables to store words and variables.
Contents of mymodule.eqx:
{ $state 10 } -> var mymodule
: mymodule:access ( -- n ) self.state ;
: mymodule:change ( n -- ) -> self.state ;
mymodule return \ make the module available Contents of myapp.eqx:
"mymodule.eqx" need -> var mymod \ require the module
mymod:access . \ prints out 10
6 mymod:change \ change state to 6
mymod:access . \ prints out 6
Equinox uses the same method call syntax as Lua, denoted by a colon (:), where an implicit self parameter is passed to refer to the module itself.
If you need multiple instances of the same type of object, you can simulate classes using Lua's metatable support.
The __index is a metatable field that allows table lookups to fall back to another table when a key is missing.
This makes it possible for multiple objects to share the same set of "methods", essentially simulating classes.
Contents of player.eqx:
{} -> var Player
: Player:new ( props -- instance )
dup { $__index self } #( setmetatable 2 0 ) ;
: Player:update ( dt -- )
dup self.vx * self.x + -> self.x
( dt ) self.vy * self.y + -> self.y ;
Player return
Contents of game.eqx:
"player.eqx" need -> var Player
{ $x 0 $y 0 $vx 10 $vy 5 } Player:new -> var player1
0.3 player1:update
player1.x . \ prints out 3
player1.y . \ prints out 1.5
Note that dot notation is used to access fields in a table. If the field is a method, it will not be called automatically.
0.3 player1:update is essentially the same as 0.3 player1 #( player1.update 1 ).