Hi. I have a binary instance for a file format[1] which describes a graph of DSP primitives. This DAG was generated from a function body[2] (in another programming language). I think that language can be boiled down to a pure language with let expressions, to allow an output to be consumed by several inputs. And there the trouble starts. I am working on this without the usual theoretical background. I am not a PLD student, I am a self-taught Haskell fan. The function body is basically a very neat way to make a DAG readable without using visualisation. Since I am blind, this topic has always fascinated me. Since I have this bidirectional binary instance, and Haskell is supposed to be great at writing small languages, I wonder what would be required to * write a decompiler which would generate a version of the original function body as a data structure and * write a compiler which would translate that data structure back to the graph. This is very much for my own learning experience, especially since there is already a Haskell library which implements at least the compilation part, and more. However, I always found it very fascinating to try to understand how this translation works, so I'd finally like to take a stab at implementing it myself. I have now searched a day for matching learning material which would shed some light on the problem for me, without any great success. Most SLC-examples I stumbled across immediately proceed to implement an evaluation fucntion, which is not quite what I need. For both directions, I need to work out the data structure for my small language first, which is where I am stuck. I have a feeling the decompiler might be easier to write then the compiler. My intuition says all I need to do is work backwards from the last graph node, resolving all inputs until I am done. However, I am stuck on the data structure and the compiler part. Any hints on what could help me to get a better grasp on the problem and how to solve it in Haskell are greatly appreciated. [1] https://github.com/mlang/sound-supercollider/blob/master/Sound/SuperCollider... [2] SynthDef(\default, { arg out=0, freq=440, amp=0.1, pan=0, gate=1; var z = LPF.ar( Mix.new( VarSaw.ar(freq + [0, Rand(-0.4,0.0), Rand(0.0,0.4)], 0, 0.3, 0.3) ), XLine.kr(Rand(4000,5000), Rand(2500,3200), 1) ) * Linen.kr(gate, 0.01, 0.7, 0.3, 2); OffsetOut.ar(out, Pan2.ar(z, pan, amp)); }, [\ir]).writeDefFile; Which translates to the following graph. The pairs are inputs, pointing at the corresponding outputs in the graph, -1 refering to the list of constants at the beginning. defaultSynthDef :: SynthDef defaultSynthDef = SynthDef [ GraphDef "default" [-0.4,0.0,0.4,0.3,4000.0,5000.0,2500.0,3200.0,1.0,1.0e-2,0.7,2.0] [0.0,440.0,0.1,0.0,1.0] [("out",0),("freq",1),("amp",2),("pan",3),("gate",4)] [ UGen "Control" Scalar 0 [] [Scalar] , UGen "Control" Control 1 [] [Control,Control,Control,Control] , UGen "VarSaw" Audio 0 [(1,0),(-1,1),(-1,3)] [Audio] , UGen "BinaryOpUGen" Audio 2 [(2,0),(-1,3)] [Audio] , UGen "Linen" Control 0 [(1,3),(-1,9),(-1,10),(-1,3),(-1,11)] [Control] , UGen "Rand" Scalar 0 [(-1,0),(-1,1)] [Scalar] , UGen "BinaryOpUGen" Control 0 [(1,0),(5,0)] [Control] , UGen "VarSaw" Audio 0 [(6,0),(-1,1),(-1,3)] [Audio] , UGen "BinaryOpUGen" Audio 2 [(7,0),(-1,3)] [Audio] , UGen "Rand" Scalar 0 [(-1,1),(-1,2)] [Scalar] , UGen "BinaryOpUGen" Control 0 [(1,0),(9,0)] [Control] , UGen "VarSaw" Audio 0 [(10,0),(-1,1),(-1,3)] [Audio] , UGen "BinaryOpUGen" Audio 2 [(11,0),(-1,3)] [Audio] , UGen "Sum3" Audio 0 [(12,0),(8,0),(3,0)] [Audio] , UGen "Rand" Scalar 0 [(-1,4),(-1,5)] [Scalar] , UGen "Rand" Scalar 0 [(-1,6),(-1,7)] [Scalar] , UGen "XLine" Control 0 [(14,0),(15,0),(-1,8),(-1,1)] [Control] , UGen "LPF" Audio 0 [(13,0),(16,0)] [Audio] , UGen "BinaryOpUGen" Audio 2 [(17,0),(4,0)] [Audio] , UGen "Pan2" Audio 0 [(18,0),(1,2),(1,1)] [Audio,Audio] , UGen "OffsetOut" Audio 0 [(0,0),(19,0),(19,1)] [] ] [] ] -- CYa, ⡍⠁⠗⠊⠕