adding lookup procs to make error handling a bit simpler

codex/blocktype.nim

@@ -14,7 +14,7 @@ import pkg/upraises
 
 push: {.upraises: [].}
 
-import pkg/libp2p/[cid, multicodec]
+import pkg/libp2p/[cid, multicodec, multihash]
 import pkg/stew/byteutils
 import pkg/questionable
 import pkg/questionable/results
@@ -37,11 +37,10 @@ type
     cid*: Cid
     data*: seq[byte]
 
-template EmptyCid*: untyped =
-  var
-    EmptyCid {.global, threadvar.}:
-      array[CIDv0..CIDv1, Table[MultiCodec, Cid]]
+var
+  EmptyCid {.threadvar.}: array[CIDv0..CIDv1, Table[MultiCodec, Cid]]
 
+template emptyCid*(version: CidVersion, codex: MultiCodec): ?!Cid =
   once:
     EmptyCid = [
       CIDv0: {
@@ -56,55 +55,61 @@ template EmptyCid*: untyped =
       }.toTable,
     ]
 
-  EmptyCid
+  try:
+    success EmptyCid[version][codex]
+  except CatchableError as exc:
+    err(exc)
 
-template EmptyDigests*: untyped =
-  var
-    EmptyDigests {.global, threadvar.}:
-      array[CIDv0..CIDv1, Table[MultiCodec, MultiHash]]
+var
+  EmptyDigests {.threadvar.}: array[CIDv0..CIDv1, Table[MultiCodec, MultiHash]]
 
+proc emptyDigest*(version: CidVersion, codex: MultiCodec): ?!MultiHash =
   once:
     EmptyDigests = [
-      CIDv0: {
-        multiCodec("sha2-256"): EmptyCid[CIDv0]
-        .catch
-        .get()[multiCodec("sha2-256")]
-        .catch
-        .get()
-        .mhash
-        .get()
-      }.toTable,
-      CIDv1: {
-        multiCodec("sha2-256"): EmptyCid[CIDv1]
-        .catch
-        .get()[multiCodec("sha2-256")]
-        .catch
-        .get()
-        .mhash
-        .get()
-      }.toTable,
-    ]
+        CIDv0: {
+          multiCodec("sha2-256"): EmptyCid[CIDv0]
+          .catch
+          .get()[multiCodec("sha2-256")]
+          .catch
+          .get()
+          .mhash
+          .get()
+        }.toTable,
+        CIDv1: {
+          multiCodec("sha2-256"): EmptyCid[CIDv1]
+          .catch
+          .get()[multiCodec("sha2-256")]
+          .catch
+          .get()
+          .mhash
+          .get()
+        }.toTable,
+      ]
 
-  EmptyDigests
+  try:
+    success EmptyDigests[version][codex]
+  except CatchableError as exc:
+    err(exc)
 
-template EmptyBlock*: untyped =
-  var
-    EmptyBlock {.global, threadvar.}:
-      array[CIDv0..CIDv1, Table[MultiCodec, Block]]
+var
+  EmptyBlock {.threadvar.}: array[CIDv0..CIDv1, Table[MultiCodec, Block]]
 
+proc emptyBlock*(version: CidVersion, codex: MultiCodec): ?!Block =
   once:
+    let cid = ? EmptyCid[CIDv0].catch
+    let sha2 = ? cid[multiCodec("sha2-256")].catch
+    let blk = Block(cid: sha2)
+
     EmptyBlock = [
-      CIDv0: {
-        multiCodec("sha2-256"): Block(
-          cid: EmptyCid[CIDv0][multiCodec("sha2-256")])
-      }.toTable,
-      CIDv1: {
-        multiCodec("sha2-256"): Block(
-          cid: EmptyCid[CIDv1][multiCodec("sha2-256")])
-      }.toTable,
+      CIDv0: { multiCodec("sha2-256"): blk }.toTable,
+      CIDv1: { multiCodec("sha2-256"): blk }.toTable,
     ]
 
-  EmptyBlock
+  try:
+    success EmptyBlock[version][codex]
+  except CatchableError as exc:
+    err(exc)
+
 
 proc isEmpty*(cid: Cid): bool =
   cid == EmptyCid[cid.cidver]

codex/manifest/manifest.nim

@@ -190,7 +190,7 @@ proc makeRoot*(self: Manifest): ?!void =
       stack.add(mh)
 
   if stack.len == 1:
-    let digest = ? EmptyDigests[self.version][self.hcodec].catch
+    let digest = ? emptyDigest(self.version, self.hcodec)
     let cid = ? Cid.init(self.version, self.codec, digest).mapFailure
 
     self.rootHash = cid.some
@@ -266,11 +266,7 @@ proc new*(
     if i < manifest.len:
       self.blocks[i] = manifest[i]
     else:
-      self.blocks[i] = EmptyCid[manifest.version]
-      .catch
-      .get()[manifest.hcodec]
-      .catch
-      .get()
+      self.blocks[i] = emptyCid(manifest.version, manifest.hcodec).get()
 
   ? self.verify()
   self.success

config.nims

@@ -63,6 +63,7 @@ else:
     # ("-fno-asynchronous-unwind-tables" breaks Nim's exception raising, sometimes)
     switch("passC", "-mno-avx512vl")
 
+--gc:orc
 --tlsEmulation:off
 --threads:on
 --opt:speed
@@ -70,7 +71,7 @@ else:
 # enable metric collection
 --define:metrics
 # for heap-usage-by-instance-type metrics and object base-type strings
---define:nimTypeNames
+# --define:nimTypeNames
 --styleCheck:usages
 --styleCheck:error