[lang] Replace array/text subtyping with overloaded dot

[rossberg]

Instead of having coercive subtyping between arrays/text and objects, treat the dot operator as overloaded.

Does not yet change the IR or compiler, other than making coercion on DotE explicit. I would imagine that after this change we might want to separate DotE from array and text accessors in the IR, as well as eliminating some code for handling the coercion more generally before.

[nomeata]

(didn’t look at the diff yet)

would imagine that after this change we might want to separate DotE from array and text accessors in the IR.

Yes! Looking forward to deleting a bunch of code I had to write :-)

In fact, we can probably desugar these projections to calls to primitive functions in desugar, and keep that syntactic device purely in the front-end.

[ggreif]

(Below is probably orthogonal to the PR.)

Will this give us for (i in [1, 2, 3]) printInt I;? Currently I get

stdin:1.11-1.20: type error, expected iterable type, but expression has type
  [Nat]

This works:

for (i in [1, 2, 3].vals()) printInt i;

[rossberg]

@ggreif, no that's orthogonal (and FWIW, I intentionally did not add that, since that would essentially be an implicit coercion).

[nomeata]

+cannot produce expected type
+  {get : Nat -> Nat}
+array.as:34.37-34.38: type error, expression of type
+  [var Nat]
+cannot produce expected type
+  {set : (Nat, Nat) -> ()}
Some tests failed.
make[1]: *** [../quick.mk:18: _out/array.done] Error 1
type-lub: [tc] [run] [run-ir] [run-low] [wasm] [wasm-run]
--- type-lub.tc (expected)
+++ type-lub.tc (actual)
@@ -0,0 +1,4 @@
+type-lub.as:6.16-6.51: warning, this array has type [Any] because elements have inconsistent types
+type-lub.as:7.17-7.50: warning, this array has type [Any] because elements have inconsistent types
+type-lub.as:8.17-8.37: warning, this array has type [Shared] because elements have inconsistent types
+type-lub.as:9.21-9.65: warning, this array has type [Any] because elements have inconsistent types
--- type-lub.run (expected)
+++ type-lub.run (actual)
@@ -0,0 +1,4 @@
+type-lub.as:6.16-6.51: warning, this array has type [Any] because elements have inconsistent types
+type-lub.as:7.17-7.50: warning, this array has type [Any] because elements have inconsistent types
+type-lub.as:8.17-8.37: warning, this array has type [Shared] because elements have inconsistent types
+type-lub.as:9.21-9.65: warning, this array has type [Any] because elements have inconsistent types
--- type-lub.run-ir (expected)
+++ type-lub.run-ir (actual)
@@ -0,0 +1,4 @@
+type-lub.as:6.16-6.51: warning, this array has type [Any] because elements have inconsistent types
+type-lub.as:7.17-7.50: warning, this array has type [Any] because elements have inconsistent types
+type-lub.as:8.17-8.37: warning, this array has type [Shared] because elements have inconsistent types
+type-lub.as:9.21-9.65: warning, this array has type [Any] because elements have inconsistent types
--- type-lub.run-low (expected)
+++ type-lub.run-low (actual)
@@ -0,0 +1,4 @@
+type-lub.as:6.16-6.51: warning, this array has type [Any] because elements have inconsistent types
+type-lub.as:7.17-7.50: warning, this array has type [Any] because elements have inconsistent types
+type-lub.as:8.17-8.37: warning, this array has type [Shared] because elements have inconsistent types
+type-lub.as:9.21-9.65: warning, this array has type [Any] because elements have inconsistent types
--- type-lub.wasm.stderr (expected)
+++ type-lub.wasm.stderr (actual)
@@ -0,0 +1,4 @@
+type-lub.as:6.16-6.51: warning, this array has type [Any] because elements have inconsistent types
+type-lub.as:7.17-7.50: warning, this array has type [Any] because elements have inconsistent types
+type-lub.as:8.17-8.37: warning, this array has type [Shared] because elements have inconsistent types
+type-lub.as:9.21-9.65: warning, this array has type [Any] because elements have inconsistent types
Some tests failed.
make[1]: *** [../quick.mk:18: _out/type-lub.done] Error 1
make[1]: Target 'quick' not remade because of errors.
make: *** [Makefile:13: quick] Error 2
builder for '/nix/store/ggfv5s9lh7147wnjayq7ncm5xr1n8bbq-tests.drv' failed with exit code 2

In case you can’t access hydra

[rossberg]

Thanks, fixed now.