rust: add rootcause as error library

Change-Id: I65460dda21331d79f0dfadfe06a7d6738c9ddefe

Cargo.lock

@@ -452,6 +452,7 @@ version = "0.0.0"
 dependencies = [
  "lix-doc",
  "regex",
+ "rootcause",
  "rustyline",
  "rustyline-derive",
  "zngur",
@@ -660,6 +661,28 @@ dependencies = [
  "rowan",
 ]
 
+[[package]]
+name = "rootcause"
+version = "0.13.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b660d9968fae12f4e691f2b2be5d9a3a6de875300c682e8d2cb89a618dd60875"
+dependencies = [
+ "hashbrown 0.17.1",
+ "indexmap",
+ "rootcause-internals",
+ "rustc-hash 2.1.3",
+ "triomphe",
+]
+
+[[package]]
+name = "rootcause-internals"
+version = "0.13.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0184f6fcff3b58b7c963aee6e3cc915c04331aa6eef974f79d7d44d21e246c24"
+dependencies = [
+ "triomphe",
+]
+
 [[package]]
 name = "rowan"
 version = "0.15.16"
@@ -668,7 +691,7 @@ checksum = "0a542b0253fa46e632d27a1dc5cf7b930de4df8659dc6e720b647fc72147ae3d"
 dependencies = [
  "countme",
  "hashbrown 0.14.5",
- "rustc-hash",
+ "rustc-hash 1.1.0",
  "text-size",
 ]
 
@@ -678,6 +701,12 @@ version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "08d43f7aa6b08d49f382cde6a7982047c3426db949b1424bc4b7ec9ae12c6ce2"
 
+[[package]]
+name = "rustc-hash"
+version = "2.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6b1e7f9a428571be2dc5bc0505c13fb6bf936822b894ec87abf8a08a4e51742d"
+
 [[package]]
 name = "rustyline"
 version = "18.0.1"
@@ -799,6 +828,12 @@ version = "1.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f18aa187839b2bdb1ad2fa35ead8c4c2976b64e4363c386d45ac0f7ee85c9233"
 
+[[package]]
+name = "triomphe"
+version = "0.1.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b40688ea6389c8171614b25491f71d4a27946e0c7ce2da1c6de27e25abf1a0ae"
+
 [[package]]
 name = "typenum"
 version = "1.20.1"

Cargo.toml

@@ -12,6 +12,7 @@ edition = "2021"
 [workspace.dependencies]
 clap = "4"
 regex = "1.12.4"
+rootcause = "0.13.0"
 rustyline = "18"
 rustyline-derive = "0.12"
 syn = "2.0"

lix/lix-rs/Cargo.toml

@@ -12,7 +12,8 @@ default = []
 
 [dependencies]
 lix-doc.path = "../lix-doc"
-regex.workspace=true
+regex.workspace = true
+rootcause.workspace=true
 rustyline.workspace = true
 rustyline-derive.workspace = true
 

lix/lix-rs/main.zng

@@ -13,6 +13,7 @@
 // in a readable and maintainable state without scattering bits of types all over the place.
 
 merge "./primitives.zng";
+merge "./rootcause.zng";
 merge "./std-common.zng";
 merge "./tuples.zng";
 

lix/lix-rs/rootcause.zng

@@ -0,0 +1,10 @@
+use ::rootcause::Report as Report;
+
+mod ::rootcause {
+	type Report {
+		#layout_conservative(size = 8, align = 8);
+		wellknown_traits(Debug);
+
+		fn to_string(&self) -> ::std::string::String;
+	}
+}