Edit tutorial by @srush.

.github/workflows/ci.yaml

@@ -51,8 +51,12 @@ jobs:
       run: rm -rf ~/.stack/setup-exe-cache
       if: runner.os == 'macOS'
 
+    - name: Build, treating warnings as errors
+      run: make build-ci
+      if: runner.os == 'Linux'
+
     - name: Build
-      run: make
+      run: make build
 
     - name: Run tests
       run: make tests

.hlint.yaml

@@ -0,0 +1,2 @@
+- arguments: [--color]
+- ignore: {name: "Use fmap"}

README.md

@@ -12,25 +12,33 @@ To learn more, check out our
 or these example programs:
 
   * [Dex prelude](https://google-research.github.io/dex-lang/prelude.html)
-  * [Mandelbrot set](https://google-research.github.io/dex-lang/mandelbrot.html)
-  * [Ray tracer](https://google-research.github.io/dex-lang/raytrace.html)
-  * [Estimating pi](https://google-research.github.io/dex-lang/pi.html)
-  * [Hamiltonian Monte Carlo](https://google-research.github.io/dex-lang/mcmc.html)
-  * [ODE integrator](https://google-research.github.io/dex-lang/ode-integrator.html)
-  * [Sierpinski triangle](https://google-research.github.io/dex-lang/sierpinski.html)
-  * [Basis function regression](https://google-research.github.io/dex-lang/regression.html)
-  * [Brownian bridge](https://google-research.github.io/dex-lang/brownian_motion.html)
-
-Please note that Dex is an experimental research project at an early stage of
-development. Contributions welcome!
+  * [Mandelbrot set](https://google-research.github.io/dex-lang/examples/mandelbrot.html)
+  * [Ray tracer](https://google-research.github.io/dex-lang/examples/raytrace.html)
+  * [Estimating pi](https://google-research.github.io/dex-lang/examples/pi.html)
+  * [Hamiltonian Monte Carlo](https://google-research.github.io/dex-lang/examples/mcmc.html)
+  * [ODE integrator](https://google-research.github.io/dex-lang/oexamples/de-integrator.html)
+  * [Sierpinski triangle](https://google-research.github.io/dex-lang/examples/sierpinski.html)
+  * [Basis function regression](https://google-research.github.io/dex-lang/examples/regression.html)
+  * [Brownian bridge](https://google-research.github.io/dex-lang/examples/brownian_motion.html)
+
+🚨 **Dex is an experimental research project at an early stage of
+development. Expect monstrous bugs and razor-sharp edges!**
+
+🤝 **Contributions welcome!** See our issue tracker for [good first issues](https://github.com/google-research/dex-lang/labels/good%20first%20issue), or browse by [thematic labels](https://github.com/google-research/dex-lang/labels).
 
 ## Dependencies
 
   * Install [stack](https://www.haskellstack.org)
   * Install LLVM 9
-    * `apt-get install llvm-9-dev` on Ubuntu/Debian,
-    * `brew install llvm@9` on macOS, and ensure it is on your `PATH` e.g. via `export PATH="$(brew --prefix llvm@9)/bin:$PATH"` before building.
-  * Install libpng (often included by default in *nix)
+    * Ubuntu/Debian: `apt-get install llvm-9-dev`
+    * macOS: `brew install llvm@9`
+      * Make sure `llvm@9` is on your `PATH` before building. Example: `export PATH="$(brew --prefix llvm@9)/bin:$PATH"`
+  * Install clang (may be installed together with llvm)
+    * Ubuntu/Debian: `apt-get install clang`
+    * macOS: installs with llvm
+  * Install libpng (often included by default in *nix platforms)
+    * Ubuntu/Debian: `apt-get install libpng-dev`
+    * macOS: `brew install libpng`
 
 ## Building
 

benchmarks/dexbench.py

@@ -55,15 +55,15 @@ def restore_machine():
 def run_benches(lang, backend):
   if lang == "dex":
     if backend == "CPU":
-      backend_args = ["--backend", "LLVM-MC"]
+      backend_args = ["--backend", "llvm-mc"]
       env = {}
     elif backend == "GPU":
-      backend_args = ["--backend", "LLVM-CUDA"]
+      backend_args = ["--backend", "llvm-cuda"]
       env = {"CUDA_LAUNCH_BLOCKING":"1"}
     else:
       raise Exception
     command = (["stack", "exec", "dex", "--"] + backend_args +
-               ["script", "--outfmt", "JSON", dex_microbench_file])
+               ["script", "--outfmt", "json", dex_microbench_file])
   elif lang == "jax":
     if backend == "CPU":
       env = {"CUDA_VISIBLE_DEVICES":""}

cabal.project

@@ -0,0 +1,13 @@
+packages:        dex.cabal
+
+source-repository-package
+    type:       git
+    location:   https://github.com/llvm-hs/llvm-hs
+    tag:        llvm-9
+    subdir:     llvm-hs
+
+source-repository-package
+    type:       git
+    location:   https://github.com/llvm-hs/llvm-hs
+    tag:        llvm-9
+    subdir:     llvm-hs-pure

dex.cabal

@@ -10,6 +10,7 @@ name:                dex
 version:             0.1.0.0
 author:              Dougal Maclaurin
 maintainer:          [email protected]
+license-file:        LICENSE
 build-type:          Simple
 
 flag cuda
@@ -32,17 +33,22 @@ library
   exposed-modules:     Env, Syntax, Type, Inference, JIT, LLVMExec,
                        Parser, Util, Imp, Imp.Embed, Imp.Optimize,
                        PPrint, Algebra, Parallelize, Optimize, Serialize
-                       Actor, Cat, Flops, Embed,
+                       Actor, Cat, Embed, Export,
                        RenderHtml, LiveOutput, Simplify, TopLevel,
-                       Autodiff, Interpreter, Logging, PipeRPC, CUDA,
+                       Autodiff, Interpreter, Logging, CUDA,
                        LLVM.JIT, LLVM.Shims
-  build-depends:       base, containers, mtl, binary, bytestring,
-                       time, tf-random, llvm-hs-pure ==9.*, llvm-hs ==9.*,
-                       aeson, megaparsec >=8.0, warp, wai, filepath,
-                       parser-combinators, http-types, prettyprinter, text,
-                       blaze-html, cmark, diagrams-lib, ansi-terminal,
-                       transformers, directory, mmap, unix,
-                       process, primitive, store, dex-resources, temporary,
+  build-depends:       base, containers, mtl, bytestring,
+                       llvm-hs-pure, llvm-hs,
+                       -- Parsing
+                       megaparsec, parser-combinators,
+                       -- Text output
+                       prettyprinter, text,
+                       -- Portable system utilities
+                       filepath, directory, ansi-terminal, process, temporary,
+                       -- Serialization
+                       store,
+                       -- Notebook support
+                       warp, wai, blaze-html, aeson, http-types, cmark, binary
   if !os(darwin)
     exposed-modules:   Resources
     hs-source-dirs:    src/resources
@@ -51,11 +57,12 @@ library
     build-depends:     dex-resources
   default-language:    Haskell2010
   hs-source-dirs:      src/lib
-  ghc-options:         -Wall -fPIC
+  ghc-options:         -Wall -fPIC -threaded -optP-Wno-nonportable-include-path
   cxx-sources:         src/lib/dexrt.cpp
   cxx-options:         -std=c++11 -fPIC
   default-extensions:  CPP, DeriveTraversable, TypeApplications, OverloadedStrings,
-                       TupleSections, ScopedTypeVariables, LambdaCase, PatternSynonyms
+                       TupleSections, ScopedTypeVariables, LambdaCase, PatternSynonyms,
+                       BlockArguments
   pkgconfig-depends:   libpng
   if flag(cuda)
     include-dirs:      /usr/local/cuda/include
@@ -71,42 +78,33 @@ executable dex
   main-is:             dex.hs
   other-extensions:    OverloadedStrings
   build-depends:       dex, base, haskeline, prettyprinter, mtl,
-                       optparse-applicative, unix, store, bytestring, directory
+                       optparse-applicative, ansi-wl-pprint,
+                       unix, store, bytestring, directory
   if os(darwin)
     build-depends:     dex-resources
   default-language:    Haskell2010
   hs-source-dirs:      src
-  default-extensions:  CPP, LambdaCase
+  default-extensions:  CPP, LambdaCase, BlockArguments
+  ghc-options:         -optP-Wno-nonportable-include-path
   if flag(optimized)
     ghc-options:       -O3
   else
     ghc-options:       -O0
 
 foreign-library Dex
   type:                native-shared
-  other-modules:       API
-  build-depends:       base, dex, dex-resources, mtl
-  hs-source-dirs:      src/foreign
-  c-sources:           src/foreign/rts.c
+  other-modules:       Dex.Foreign.API, Dex.Foreign.Util, Dex.Foreign.JIT
+                     , Dex.Foreign.Context, Dex.Foreign.Serialize
+  build-depends:       base, mtl, containers, llvm-hs, dex, dex-resources
+  if os(darwin)
+    build-depends:     dex-resources
+  hs-source-dirs:      src/
+  c-sources:           src/Dex/Foreign/rts.c
   cc-options:          -std=c11 -fPIC
-  ghc-options:         -Wall -fPIC
-  default-language:    Haskell2010
-  default-extensions:  TypeApplications, ScopedTypeVariables, LambdaCase
-  if flag(optimized)
-    ghc-options:       -O3
-  else
-    ghc-options:       -O0
-
-Test-Suite test-dex
-  type:                exitcode-stdio-1.0
-  main-is:             PropTests.hs
-  build-depends:       dex, base, prettyprinter, containers,
-                       hedgehog, microlens-platform, mtl
-  other-modules:       GenExpr, TestPass
+  ghc-options:         -Wall -fPIC -optP-Wno-nonportable-include-path
   default-language:    Haskell2010
-  hs-source-dirs:      tests
-  ghc-options:         cbits/libdex.so
-                       -Wall
+  default-extensions:  TypeApplications, ScopedTypeVariables, LambdaCase,
+                       BlockArguments
   if flag(optimized)
     ghc-options:       -O3
   else

examples/brownian_motion.dx

@@ -1,22 +1,22 @@
 
+include "plot.dx"
 
 UnitInterval = Float
 
-bmIter : (Key & Float & Float & UnitInterval) -> (Key & Float & Float & UnitInterval) =
-  \(key, y, sigma, t).
-    (kDraw, kL, kR) = splitKey3 key
-    t' = abs (t - 0.5)
-    y' = sigma * randn kDraw * (0.5 - t')
-    key' = select (t > 0.5) kL kR
-    (key', y + y', sigma / sqrt 2.0, t' * 2.0)
+def bmIter ((key, y, sigma, t):(Key & Float & Float & UnitInterval)) :
+                               (Key & Float & Float & UnitInterval) =
+  [kDraw, kL, kR] = splitKey key
+  t' = abs (t - 0.5)
+  y' = sigma * randn kDraw * (0.5 - t')
+  key' = select (t > 0.5) kL kR
+  (key', y + y', sigma / sqrt 2.0, t' * 2.0)
 
-sampleBM : Key -> UnitInterval -> Float =
-  \key t.
-    (_, y, _, _) = fold (key, 0.0, 1.0, t) \i:(Fin 10). bmIter
-    y
+def sampleBM (key:Key) (t:UnitInterval) : Float =
+  (_, y, _, _) = fold (key, 0.0, 1.0, t) \i:(Fin 10). bmIter
+  y
 
 xs = linspace (Fin 1000) 0.0 1.0
 ys = map (sampleBM (newKey 0)) xs
 
--- :plot zip xs ys
--- > <html output>
+:html showPlot $ xyPlot xs ys
+> <html output>