Reason edition: snippets chapter 3.5

Author: fhammerschmidt

src/Makefile

@@ -55,7 +55,7 @@ ocaml: suffix='-ocaml'
 ocaml: clean out-dir version.tex $(OCAMLPDF)
 
 reason: suffix='-reason'
-reason: out-dir version.tex $(REASONPDF)
+reason: clean out-dir version.tex $(REASONPDF)
 
 # Main targets
 $(TOPPDFFILES) : %.pdf : %.tex $(TEXFILES)

src/content/3.5/code/reason/snippet01.re

@@ -0,0 +1,6 @@
+module List_Monad: Monad_Join = {
+  type m('a) = list('a);
+
+  let join = List.concat;
+  let return = a => [a];
+};

src/content/3.5/code/reason/snippet02.re

@@ -0,0 +1 @@
+let (>>=) = (xs, k) => List.concat(List.map(k, xs));

src/content/3.5/code/reason/snippet03.re

@@ -0,0 +1,13 @@
+module Pythagorean = {
+  let ( let* ) = Fn.flip(Gen.flat_map);
+  let (let+) = (x, f) => Gen.map(f, x);
+  let guard = b => b ? Gen.return() ? Gen.empty;
+
+  let triples = {
+    let* z = Gen.init(i => i + 1);
+    let* x = Gen.init(~limit=z, i => i + 1);
+    let* y = Gen.init(~limit=z, i => i + x);
+    let+ _ = guard(x * x + y * y == z * z);
+    Gen.return((x, y, z));
+  };
+};

src/content/3.5/code/reason/snippet04.re

@@ -0,0 +1,4 @@
+let guard =
+  fun
+  | true => [()]
+  | false => [];

src/content/3.5/code/reason/snippet05.re

@@ -0,0 +1,16 @@
+module Pythagorean = {
+  let ( let* ) = Fn.flip(Gen.flat_map);
+  let (let+) = (x, f) => Gen.map(f, x);
+  let guard = b => b ? Gen.return() : Gen.empty;
+
+  let triples = {
+    let* z = Gen.init(i => i + 1);
+    let* x = Gen.init(~limit=z, i => i + 1);
+    let* y = Gen.init(~limit=z, i => i + x);
+    if (x * x + y * y == z * z) {
+      Gen.return((x, y, z));
+    } else {
+      Gen.empty;
+    };
+  };
+};

src/content/3.5/code/reason/snippet06.re

@@ -0,0 +1,2 @@
+type reader('e, 'a) =
+  | Reader('e => 'a);

src/content/3.5/code/reason/snippet07.re

@@ -0,0 +1 @@
+let run_reader = (Reader(f), e) => f(e);

src/content/3.5/code/reason/snippet08.re

@@ -0,0 +1 @@
+let (>>=) = (ra, k) => Reader(e => ...);

src/content/3.5/code/reason/snippet09.re

@@ -0,0 +1,4 @@
+let (>>=) = (ra, k) => Reader(e => {
+  let a = run_reader(ra, e);
+  ...
+});