5001 - drop the :(scenario) DSL

I've been saying for a while[1][2][3] that adding extra abstractions makes
things harder for newcomers, and adding new notations doubly so. And then
I notice this DSL in my own backyard. Makes me feel like a hypocrite.

[1] https://news.ycombinator.com/item?id=13565743#13570092
[2] https://lobste.rs/s/to8wpr/configuration_files_are_canary_warning
[3] https://lobste.rs/s/mdmcdi/little_languages_by_jon_bentley_1986#c_3miuf2

The implementation of the DSL was also highly hacky:

a) It was happening in the tangle/ tool, but was utterly unrelated to tangling
layers.

b) There were several persnickety constraints on the different kinds of
lines and the specific order they were expected in. I kept finding bugs
where the translator would silently do the wrong thing. Or the error messages
sucked, and readers may be stuck looking at the generated code to figure
out what happened. Fixing error messages would require a lot more code,
which is one of my arguments against DSLs in the first place: they may
be easy to implement, but they're hard to design to go with the grain of
the underlying platform. They require lots of iteration. Is that effort
worth prioritizing in this project?

On the other hand, the DSL did make at least some readers' life easier,
the ones who weren't immediately put off by having to learn a strange syntax.
There were fewer quotes to parse, fewer backslash escapes.

Anyway, since there are also people who dislike having to put up with strange
syntaxes, we'll call that consideration a wash and tear this DSL out.

---

This commit was sheer drudgery. Hopefully it won't need to be redone with
a new DSL because I grow sick of backslashes.

1 files changed, 63 insertions, 42 deletions

diff --git a/036abandon.cc b/036abandon.cc
index 4dcf572f..a1f66523 100644
--- a/036abandon.cc
+++ b/036abandon.cc
@@ -1,16 +1,21 @@
 //: Reclaiming memory when it's no longer used.
 
-:(scenario new_reclaim)
-def main [
-  10:&:num <- new number:type
-  20:num <- deaddress 10:&:num
-  abandon 10:&:num
-  30:&:num <- new number:type  # must be same size as abandoned memory to reuse
-  40:num <- deaddress 30:&:num
-  50:bool <- equal 20:num, 40:num
-]
-# both allocations should have returned the same address
-+mem: storing 1 in location 50
+void test_new_reclaim() {
+  run(
+      "def main [\n"
+      "  10:&:num <- new number:type\n"
+      "  20:num <- deaddress 10:&:num\n"
+      "  abandon 10:&:num\n"
+      "  30:&:num <- new number:type\n"  // must be same size as abandoned memory to reuse
+      "  40:num <- deaddress 30:&:num\n"
+      "  50:bool <- equal 20:num, 40:num\n"
+      "]\n"
+  );
+  CHECK_TRACE_CONTENTS(
+      // both allocations should have returned the same address
+      "mem: storing 1 in location 50\n"
+  );
+}
 
 //: When abandoning addresses we'll save them to a 'free list', segregated by size.
 
@@ -97,36 +102,52 @@ if (get_or_insert(Current_routine->free_list, size)) {
   return result;
 }
 
-:(scenario new_differing_size_no_reclaim)
-def main [
-  1:&:num <- new number:type
-  2:num <- deaddress 1:&:num
-  abandon 1:&:num
-  3:&:@:num <- new number:type, 2  # different size
-  4:num <- deaddress 3:&:@:num
-  5:bool <- equal 2:num, 4:num
-]
-# no reuse
-+mem: storing 0 in location 5
+:(code)
+void test_new_differing_size_no_reclaim() {
+  run(
+      "def main [\n"
+      "  1:&:num <- new number:type\n"
+      "  2:num <- deaddress 1:&:num\n"
+      "  abandon 1:&:num\n"
+      "  3:&:@:num <- new number:type, 2\n"  // different size
+      "  4:num <- deaddress 3:&:@:num\n"
+      "  5:bool <- equal 2:num, 4:num\n"
+      "]\n"
+  );
+  CHECK_TRACE_CONTENTS(
+      // no reuse
+      "mem: storing 0 in location 5\n"
+  );
+}
 
-:(scenario new_reclaim_array)
-def main [
-  10:&:@:num <- new number:type, 2
-  20:num <- deaddress 10:&:@:num
-  abandon 10:&:@:num
-  30:&:@:num <- new number:type, 2  # same size
-  40:num <- deaddress 30:&:@:num
-  50:bool <- equal 20:num, 40:num
-]
-# both calls to new returned identical addresses
-+mem: storing 1 in location 50
+void test_new_reclaim_array() {
+  run(
+      "def main [\n"
+      "  10:&:@:num <- new number:type, 2\n"
+      "  20:num <- deaddress 10:&:@:num\n"
+      "  abandon 10:&:@:num\n"
+      "  30:&:@:num <- new number:type, 2\n"  // same size
+      "  40:num <- deaddress 30:&:@:num\n"
+      "  50:bool <- equal 20:num, 40:num\n"
+      "]\n"
+  );
+  CHECK_TRACE_CONTENTS(
+      // both calls to new returned identical addresses
+      "mem: storing 1 in location 50\n"
+  );
+}
 
-:(scenario lookup_of_abandoned_address_raises_error)
-% Hide_errors = true;
-def main [
-  1:&:num <- new num:type
-  3:&:num <- copy 1:&:num
-  abandon 1:&:num
-  5:num/raw <- copy *3:&:num
-]
-+error: main: address is already abandoned in '5:num/raw <- copy *3:&:num'
+void test_lookup_of_abandoned_address_raises_error() {
+  Hide_errors = true;
+  run(
+      "def main [\n"
+      "  1:&:num <- new num:type\n"
+      "  3:&:num <- copy 1:&:num\n"
+      "  abandon 1:&:num\n"
+      "  5:num/raw <- copy *3:&:num\n"
+      "]\n"
+  );
+  CHECK_TRACE_CONTENTS(
+      "error: main: address is already abandoned in '5:num/raw <- copy *3:&:num'\n"
+  );
+}