From 21f59078d5e8ec5e4311ac38b9f72fb104220eb6 Mon Sep 17 00:00:00 2001
From: Cesar Roux Dit Buisson <cr1013@imperial.ac.uk>
Date: Wed, 16 Sep 2015 16:26:24 +0100
Subject: [PATCH] Change interpreter example to calc with stack example
---
generator/tests/calc.ml | 2 +-
interp.js | 238 +++++++++++++++++++++++++++++++---------
source.js | 4 +-
3 files changed, 192 insertions(+), 52 deletions(-)
diff --git a/generator/tests/calc.ml b/generator/tests/calc.ml
index 62caab4..1a288a0 100644
--- a/generator/tests/calc.ml
+++ b/generator/tests/calc.ml
@@ -37,5 +37,5 @@ and print_sexpr sexpr = match sexpr with
let f =
(*let bli = Stack.C(1, Stack.N) in
let blii = (Stack.push 2 bli) in*)
- let source = parse "Pop(Push(1, Push(5, Emp))) - 7" in
+ let source = parse "Pop(Push(1, Push(5, Emp)) - 7" in
print ((print_expr source) + " = " + to_string (eval_ source))
diff --git a/interp.js b/interp.js
index ab8797f..637cdc4 100644
--- a/interp.js
+++ b/interp.js
@@ -254,39 +254,152 @@ function run_trm(expr) {
var ctx = ctx_empty();
ctx = ctx_push(ctx, "expr", expr, "term");
log(1, ctx, "run_trm");
- return (function () {
- switch (expr.type) {
- case "Const": var n = expr.value;
- ctx_push(ctx, "n", n, "value");
- log(5 , ctx, "Const");
-
- return n;
- case "Add": var ls = expr.left, rs = expr.right;
- ctx_push(ctx, "ls", ls, "value");
- ctx_push(ctx, "rs", rs, "value");
- log(8 , ctx, "Add");
-
- return run_trm_wrap(10, ls) + run_trm_wrap(10, rs);
- case "Sub": var ls = expr.left, rs = expr.right;
- ctx_push(ctx, "ls", ls, "value");
- ctx_push(ctx, "rs", rs, "value");
- log(11 , ctx, "Sub");
-
- return run_trm_wrap(13, ls) - run_trm_wrap(13, rs);
- case "Mul": var ls = expr.left, rs = expr.right;
- ctx_push(ctx, "ls", ls, "value");
- ctx_push(ctx, "rs", rs, "value");
- log(14 , ctx, "Mul");
-
- return run_trm_wrap(16, ls) * run_trm_wrap(13, rs);
- case "Div": var ls = expr.left, rs = expr.right;
- ctx_push(ctx, "ls", ls, "value");
- ctx_push(ctx, "rs", rs, "value");
- log(17 , ctx, "Div");
-
- return run_trm_wrap(19, ls) / run_trm_wrap(19, rs);
- }
- }())
+ return (function (expr) {
+ var Stack = {
+ is_empty: function (s) {
+ return s === {type: "N"};
+ },
+
+ push: function (x, stack) {
+ return {type: "C", value: x, stack: stack};
+ },
+
+ pop: function (stack) {
+ return (function () {
+ switch (stack.type) {
+ case "C": var x = stack.value, xs = stack.stack;
+ return x;
+ case "K": var x = stack.value, xs = stack.stack;
+ return x;
+ case "B":
+ return stuck("Empty list");
+ case "N":
+ return stuck("Empty list");
+ }
+ }())
+ ;
+ },
+
+ }
+
+ var eval_ = function (expr) {
+ return (function () {
+ switch (expr.type) {
+ case "Const": var n = expr.value;
+ ctx_push(ctx, "n", n, "value");
+ log(30 , ctx, "Const");
+
+ return n;
+ case "Add": var ls = expr.left, rs = expr.right;
+ ctx_push(ctx, "ls", ls, "value");
+ ctx_push(ctx, "rs", rs, "value");
+ log(32 , ctx, "Add");
+
+ return eval_(ls) + eval_(rs);
+ case "Sub": var ls = expr.left, rs = expr.right;
+ ctx_push(ctx, "ls", ls, "value");
+ ctx_push(ctx, "rs", rs, "value");
+ log(34 , ctx, "Sub");
+
+ return eval_(ls) - eval_(rs);
+ case "Mul": var ls = expr.left, rs = expr.right;
+ ctx_push(ctx, "ls", ls, "value");
+ ctx_push(ctx, "rs", rs, "value");
+ log(36 , ctx, "Mul");
+
+ return eval_(ls) * eval_(rs);
+ case "Div": var ls = expr.left, rs = expr.right;
+ ctx_push(ctx, "ls", ls, "value");
+ ctx_push(ctx, "rs", rs, "value");
+ log(38 , ctx, "Div");
+
+ return eval_(ls) / eval_(rs);
+ case "Pop": var s = expr.stack;
+ ctx_push(ctx, "s", s, "value");
+ log(40 , ctx, "Pop");
+
+ return Stack.pop(evals(s));
+ }
+ }())
+ ;
+ };
+
+ var evals = function (sexpr) {
+ return (function () {
+ switch (sexpr.type) {
+ case "Emp":
+ return {type: "Stack.N"};
+ case "Push": var v = sexpr.value, s = sexpr.stack;
+ ctx_push(ctx, "v", v, "value");
+ ctx_push(ctx, "s", s, "value");
+ log(52 , ctx, "Push");
+
+ return Stack.push(eval_(v), evals(s));
+ }
+ }())
+ ;
+ };
+
+ var print_expr = function (expr) {
+ return (function () {
+ switch (expr.type) {
+ case "Const": var n = expr.value;
+ ctx_push(ctx, "n", n, "value");
+ log(62 , ctx, "Const");
+
+ return to_string(n);
+ case "Add": var ls = expr.left, rs = expr.right;
+ ctx_push(ctx, "ls", ls, "value");
+ ctx_push(ctx, "rs", rs, "value");
+ log(64 , ctx, "Add");
+
+ return "(" + print_expr(ls) + ")" + " + " + print_expr(rs);
+ case "Sub": var ls = expr.left, rs = expr.right;
+ ctx_push(ctx, "ls", ls, "value");
+ ctx_push(ctx, "rs", rs, "value");
+ log(66 , ctx, "Sub");
+
+ return "(" + print_expr(ls) + ")" + " - " + print_expr(rs);
+ case "Mul": var ls = expr.left, rs = expr.right;
+ ctx_push(ctx, "ls", ls, "value");
+ ctx_push(ctx, "rs", rs, "value");
+ log(68 , ctx, "Mul");
+
+ return "(" + print_expr(ls) + ")" + " * " + print_expr(rs);
+ case "Div": var ls = expr.left, rs = expr.right;
+ ctx_push(ctx, "ls", ls, "value");
+ ctx_push(ctx, "rs", rs, "value");
+ log(70 , ctx, "Div");
+
+ return "(" + print_expr(ls) + ")" + " / " + print_expr(rs);
+ case "Pop": var s = expr.stack;
+ ctx_push(ctx, "s", s, "value");
+ log(72 , ctx, "Pop");
+
+ return "Pop(" + print_sexpr(s) + ")";
+ }
+ }())
+ ;
+ };
+
+ var print_sexpr = function (sexpr) {
+ return (function () {
+ switch (sexpr.type) {
+ case "Emp":
+ return "Emp";
+ case "Push": var v = sexpr.value, s = sexpr.stack;
+ ctx_push(ctx, "v", v, "value");
+ ctx_push(ctx, "s", s, "value");
+ log(84 , ctx, "Push");
+
+ return "Push(" + print_expr(v) + ", " + print_sexpr(s) + ")";
+ }
+ }())
+ ;
+ };
+
+ return eval_(expr);
+ }(expr))
;
};
@@ -363,31 +476,58 @@ var parse = function (source) {
var ast = esprima.parse(source).body[0].expression;
function transform (tree) {
- if (tree === undefined) {
- } else {
+ if (tree === undefined) {
+ } else {
+ // Javascript style instructions are well handled with no additional creation.
switch (tree.operator) {
- case '+':
- tree.type = "Add"; tree.operator = undefined; break;
- case '-':
- tree.type = "Sub"; tree.operator = undefined; break;
- case "*":
- tree.type = "Mul"; tree.operator = undefined; break;
- case "/":
- tree.type = "Div"; tree.operator = undefined; break;
- default: break;
+ case '+':
+ tree.type = "Add"; tree.operator = undefined; break;
+ case '-':
+ tree.type = "Sub"; tree.operator = undefined; break;
+ case "*":
+ tree.type = "Mul"; tree.operator = undefined; break;
+ case "/":
+ tree.type = "Div"; tree.operator = undefined; break;
+ default: break;
}
- switch (tree.type) {
- case "Literal":
- tree.type = "Const"; break;
- default: break;
+ if (tree.type === "Literal") {
+ tree.type = "Const";
}
+ // tree.left and tree.right from parser interpretation
if (tree.left !== undefined) tree.left = transform(tree.left);
if (tree.right !== undefined) tree.right = transform(tree.right);
+
+ // Esprima sees these standalone type instructions as Identifiers
+ if (tree.type === "Identifier") {
+ switch (tree.name) {
+ case "Emp":
+ tree.type = "Emp"; break;
+ default: console.log("Unknown ident"); break;
+ }
+ }
+
+ // Esprima generates a function type structure that needs reshaping to the
+ // automatically generated structure, respecting label names!
+ if (tree.type === "CallExpression") {
+ switch (tree.callee.name) {
+ case "Push":
+ tree.type = "Push";
+ tree.value = transform(tree.arguments[0]);
+ tree.stack = transform(tree.arguments[1]);
+ break;
+ case "Pop":
+ tree.type = "Pop";
+ tree.stack = transform(tree.arguments[0]);
+ break;
+ default: console.log("Unknown callexpr"); break;
+ }
+ }
+
return tree;
+ }
}
- }
return transform(ast);
}
diff --git a/source.js b/source.js
index 951872d..55ffdc7 100644
--- a/source.js
+++ b/source.js
@@ -1,13 +1,13 @@
// Source file loaded initially
-var source_file = '((1972 / 29) / 2) + 8';
+var source_file = 'Pop(Push(1, Push(5, Emp))) - 7';
// Source code for the interpreter
// This code was generated from the code placed in comments in "interp.js",
// which was itself obtained by dropping the "log" and "ctx" lines from
// the instrumented interpreter just above.
var tracer_files = [
- { file: 'interp.js', contents: 'function run_trm(expr) {\n var ctx = ctx_empty();\n return (function () {\n switch (expr.type) {\n case "Const": var n = expr.value;\n\n return n;\n case "Add": var ls = expr.left, rs = expr.right;\n\n return run_trm(ls) + run_trm(rs);\n case "Sub": var ls = expr.left, rs = expr.right;\n\n return run_trm(ls) - run_trm(rs);\n case "Mul": var ls = expr.left, rs = expr.right;\n\n return run_trm(ls) * run_trm(rs);\n case "Div": var ls = expr.left, rs = expr.right;\n\n return run_trm(ls) / run_trm(rs);\n }\n }());\n };'
+ { file: 'interp.js', contents: 'var Stack = {\n is_empty: function (s) {\n return s === {type: "N"};\n },\n\n push: function (x, stack) {\n return {type: "C", value: x, stack: stack};\n },\n\n pop: function (stack) {\n return (function () {\n switch (stack.type) {\n case "C": var x = stack.value, xs = stack.stack;\n return x;\n case "K": var x = stack.value, xs = stack.stack;\n return x;\n case "B": \n return stuck("Empty list");\n case "N": \n return stuck("Empty list");\n }\n }())\n ;\n },\n\n}\nvar eval_ = function (expr) {\n return (function () {\n switch (expr.type) {\n case "Const": var n = expr.value;\n return n;\n case "Add": var ls = expr.left, rs = expr.right;\n return eval_(ls) + eval_(rs);\n case "Sub": var ls = expr.left, rs = expr.right;\n return eval_(ls) - eval_(rs);\n case "Mul": var ls = expr.left, rs = expr.right;\n return eval_(ls) * eval_(rs);\n case "Div": var ls = expr.left, rs = expr.right;\n return eval_(ls) / eval_(rs);\n case "Pop": var s = expr.stack;\n return Stack.pop(evals(s));\n }\n }())\n ;\n };\n \nvar evals = function (sexpr) {\n return (function () {\n switch (sexpr.type) {\n case "Emp": \n return {type: "Stack.N"};\n case "Push": var v = sexpr.value, s = sexpr.stack;\n return Stack.push(eval_(v), evals(s));\n }\n }())\n ;\n};\n\nvar print_expr = function (expr) {\n return (function () {\n switch (expr.type) {\n case "Const": var n = expr.value;\n return to_string(n);\n case "Add": var ls = expr.left, rs = expr.right;\n return "(" + print_expr(ls) + ")" + " + " + print_expr(rs);\n case "Sub": var ls = expr.left, rs = expr.right;\n return "(" + print_expr(ls) + ")" + " - " + print_expr(rs);\n case "Mul": var ls = expr.left, rs = expr.right;\n return "(" + print_expr(ls) + ")" + " * " + print_expr(rs);\n case "Div": var ls = expr.left, rs = expr.right;\n return "(" + print_expr(ls) + ")" + " / " + print_expr(rs);\n case "Pop": var s = expr.stack;\n return "Pop(" + print_sexpr(s) + ")";\n }\n }())\n ;\n};\n\nvar print_sexpr = function (sexpr) {\n return (function () {\n switch (sexpr.type) {\n case "Emp": \n return "Emp";\n case "Push": var v = sexpr.value, s = sexpr.stack;\n return "Push(" + print_expr(v) + ", " + print_sexpr(s) + ")";\n }\n }())\n ;\n};\n\nreturn eval_(expr);'
}
]
--
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