2735 - define recipes using 'def'

I'm dropping all mention of 'recipe' terminology from the Readme. That
way I hope to avoid further bike-shedding discussions while I very
slowly decide on the right terminology with my students.

I could be smarter in my error messages and use 'recipe' when code uses
it and 'function' otherwise. But what about other words like ingredient?
It would all add complexity that I'm not yet sure is worthwhile. But I
do want separate experiences for veteran programmers reading about Mu on
github and for people learning programming using Mu.

1 files changed, 30 insertions, 29 deletions

diff --git a/036call_reply.cc b/036call_reply.cc
index ba0c0a41..299abf10 100644
--- a/036call_reply.cc
+++ b/036call_reply.cc
@@ -1,10 +1,10 @@
-//: Calls can also generate products, using 'reply'.
+//: Calls can also generate products, using 'reply' or 'return'.
 
 :(scenario reply)
-recipe main [
+def main [
   1:number, 2:number <- f 34
 ]
-recipe f [
+def f [
   12:number <- next-ingredient
   13:number <- add 1, 12:number
   reply 12:number, 13:number
@@ -16,6 +16,7 @@ recipe f [
 REPLY,
 :(before "End Primitive Recipe Numbers")
 put(Recipe_ordinal, "reply", REPLY);
+put(Recipe_ordinal, "return", REPLY);
 :(before "End Primitive Recipe Checks")
 case REPLY: {
   break;  // checks will be performed by a transform below
@@ -46,13 +47,13 @@ case REPLY: {
 
 //: Products can include containers and exclusive containers, addresses and arrays.
 :(scenario reply_container)
-recipe main [
+def main [
   3:point <- f 2
 ]
-recipe f [
+def f [
   12:number <- next-ingredient
   13:number <- copy 35
-  reply 12:point/raw
+  return 12:point/raw
 ]
 +run: result 0 is [2, 35]
 +mem: storing 2 in location 3
@@ -86,7 +87,7 @@ void check_types_of_reply_instructions(recipe_ordinal r) {
         reagent rhs = caller_instruction.products.at(i);
         canonize_type(rhs);
         if (!types_coercible(rhs, lhs)) {
-          raise << maybe(callee.name) << "reply ingredient " << lhs.original_string << " can't be saved in " << rhs.original_string << '\n' << end();
+          raise << maybe(callee.name) << reply_inst.name << " ingredient " << lhs.original_string << " can't be saved in " << rhs.original_string << '\n' << end();
           raise << to_string(lhs.type) << " vs " << to_string(rhs.type) << '\n' << end();
           goto finish_reply_check;
         }
@@ -117,16 +118,16 @@ void check_types_of_reply_instructions(recipe_ordinal r) {
 
 :(scenario reply_type_mismatch)
 % Hide_errors = true;
-recipe main [
+def main [
   3:number <- f 2
 ]
-recipe f [
+def f [
   12:number <- next-ingredient
   13:number <- copy 35
   14:point <- copy 12:point/raw
-  reply 14:point
+  return 14:point
 ]
-+error: f: reply ingredient 14:point can't be saved in 3:number
++error: f: return ingredient 14:point can't be saved in 3:number
 
 //: In mu we'd like to assume that any instruction doesn't modify its
 //: ingredients unless they're also products. The /same-as-ingredient inside
@@ -135,24 +136,24 @@ recipe f [
 
 :(scenario reply_same_as_ingredient)
 % Hide_errors = true;
-recipe main [
+def main [
   1:number <- copy 0
   2:number <- test1 1:number  # call with different ingredient and product
 ]
-recipe test1 [
+def test1 [
   10:number <- next-ingredient
-  reply 10:number/same-as-ingredient:0
+  return 10:number/same-as-ingredient:0
 ]
 +error: main: '2:number <- test1 1:number' should write to 1:number rather than 2:number
 
 :(scenario reply_same_as_ingredient_dummy)
-recipe main [
+def main [
   1:number <- copy 0
   _ <- test1 1:number  # call with different ingredient and product
 ]
-recipe test1 [
+def test1 [
   10:number <- next-ingredient
-  reply 10:number/same-as-ingredient:0
+  return 10:number/same-as-ingredient:0
 ]
 $error: 0
 
@@ -176,22 +177,22 @@ string to_string(const vector<double>& in) {
 //: Conditional reply.
 
 :(scenario reply_if)
-recipe main [
+def main [
   1:number <- test1
 ]
-recipe test1 [
-  reply-if 0, 34
-  reply 35
+def test1 [
+  return-if 0, 34
+  return 35
 ]
 +mem: storing 35 in location 1
 
 :(scenario reply_if_2)
-recipe main [
+def main [
   1:number <- test1
 ]
-recipe test1 [
-  reply-if 1, 34
-  reply 35
+def test1 [
+  return-if 1, 34
+  return 35
 ]
 +mem: storing 34 in location 1
 
@@ -201,7 +202,7 @@ recipe test1 [
 //   jump-unless a, 1:offset
 //   reply b, c, ...
 //   ```
-if (curr.name == "reply-if") {
+if (curr.name == "reply-if" || curr.name == "return-if") {
   if (curr.products.empty()) {
     curr.operation = get(Recipe_ordinal, "jump-unless");
     curr.name = "jump-unless";
@@ -216,7 +217,7 @@ if (curr.name == "reply-if") {
     curr.ingredients.swap(results);
   }
   else {
-    raise << "'reply-if' never yields any products\n" << end();
+    raise << "'" << curr.name << "' never yields any products\n" << end();
   }
 }
 // rewrite `reply-unless a, b, c, ...` to
@@ -224,7 +225,7 @@ if (curr.name == "reply-if") {
 //   jump-if a, 1:offset
 //   reply b, c, ...
 //   ```
-if (curr.name == "reply-unless") {
+if (curr.name == "reply-unless" || curr.name == "return-unless") {
   if (curr.products.empty()) {
     curr.operation = get(Recipe_ordinal, "jump-if");
     curr.name = "jump-if";
@@ -239,6 +240,6 @@ if (curr.name == "reply-unless") {
     curr.ingredients.swap(results);
   }
   else {
-    raise << "'reply-unless' never yields any products\n" << end();
+    raise << "'" << curr.name << "' never yields any products\n" << end();
   }
 }