Refactor NbBlock

sandbox/hugoop/one.nim

@@ -0,0 +1,32 @@
+import jsony
+
+type
+  Nimib = ref object of RootObj
+    a, b, c: int
+  NimibChild = ref object of Nimib
+    d, e: float
+
+
+method dump(n: Nimib): string =
+  n[].toJson()
+
+when not defined(noNimibChild): # essential, see below
+  method dump(n: NimibChild): string =
+    n[].toJson()
+
+proc dumpHook*(s: var string, v: Nimib) =
+  s.add v.dump()
+
+let n1: Nimib = Nimib(a: 1, b: 2, c: 3)
+let n2: Nimib = NimibChild(d: 3.14, e: 4.56)
+
+echo n1.toJson()
+echo n2.toJson()
+#[ nim r one
+{"a":1,"b":2,"c":3}
+{"d":3.14,"e":4.56,"a":0,"b":0,"c":0}
+]#
+#[ nim -d:noNimibChild r one
+{"a":1,"b":2,"c":3}
+{"a":0,"b":0,"c":0}
+]#

sandbox/hugoop/three.nim

@@ -0,0 +1,51 @@
+import jsony, tables
+
+type
+  Nimib = ref object of RootObj
+    a, b, c: int
+    typename: string
+  NimibChild = ref object of Nimib
+    d, e: float
+
+var parseDefs: Table[string, proc (s: string, i: var int): Nimib]
+
+template registerBlock(typename: untyped) =
+  parseDefs[$typename] =
+    proc (s: string, i: var int): Nimib =
+      var v: typename
+      new v
+      parseHook(s, i, v[])
+      result = v
+
+  method dump(n: typename): string =
+    n[].toJson()
+
+proc parseHook*(s: string, i: var int, v: var Nimib) =
+  # First parse the typename
+  var n: Nimib = Nimib()
+  let current_i = i
+  parseHook(s, i, n[])
+  # Reset i
+  i = current_i
+  # Parse the correct type
+  let typename = n.typename
+  v = parseDefs[typename](s, i)
+
+registerBlock(Nimib)
+registerBlock(NimibChild)
+
+# moved this here, I do not need to add dummy dumphook
+proc dumpHook*(s: var string, v: Nimib) =
+  s.add v.dump()
+
+
+let n1: Nimib = Nimib(a: 1, b: 2, c: 3, typename: "Nimib")
+let n2: Nimib = NimibChild(a: 100, d: 3.14, e: 4.56, typename: "NimibChild")
+
+echo n1.toJson()
+echo n2.toJson()
+
+let s1 = n1.toJson().fromJson(Nimib)
+echo s1.toJson()
+let s2 = n2.toJson().fromJson(Nimib)
+echo s2.toJson()

sandbox/hugoop/two.nim

@@ -0,0 +1,51 @@
+import jsony, tables
+
+type
+  Nimib = ref object of RootObj
+    a, b, c: int
+    typename: string
+  NimibChild = ref object of Nimib
+    d, e: float
+
+method dump(n: Nimib): string =
+  n[].toJson()
+
+method dump(n: NimibChild): string =
+  n[].toJson()
+
+proc dumpHook*(s: var string, v: Nimib) =
+  s.add v.dump()
+
+let n1: Nimib = Nimib(a: 1, b: 2, c: 3, typename: "Nimib")
+let n2: Nimib = NimibChild(a: 100, d: 3.14, e: 4.56, typename: "NimibChild")
+
+echo n1.toJson()
+echo n2.toJson()
+
+proc parseNimib(s: string, i: var int): Nimib =
+  var v = Nimib()
+  parseHook(s, i, v[])
+  result = v
+
+proc parseNimibChild(s: string, i: var int): Nimib =
+  var v = NimibChild()
+  parseHook(s, i, v[])
+  result = v
+
+let parseDefs = {
+  "Nimib": parseNimib,
+  "NimibChild": parseNimibChild
+}.toTable()
+
+proc parseHook*(s: string, i: var int, v: var Nimib) =
+  var n: Nimib = Nimib()
+  let current_i = i
+  parseHook(s, i, n[])
+  i = current_i
+  let typename = n.typename
+  v = parseDefs[typename](s, i)
+
+let s1 = n1.toJson().fromJson(Nimib)
+echo s1.toJson()
+let s2 = n2.toJson().fromJson(Nimib)
+echo s2.toJson()

sandbox/minib/capture.nim

@@ -0,0 +1,30 @@
+## This submodule implements only one template to temporarily redirect and capture stdout during execution of a chunk of code.
+import tempfile
+
+# see https://stackoverflow.com/questions/64026829/how-to-temporarily-capture-stdout
+# Thanks, Clonk!
+
+# low level, should be Posix only but they happen to work on (my) Windows, too!
+proc dup(oldfd: FileHandle): FileHandle {.importc, header: "unistd.h".}
+proc dup2(oldfd: FileHandle, newfd: FileHandle): cint {.importc, header: "unistd.h".}
+
+template captureStdout*(ident: untyped, body: untyped) =
+  ## redirect stdout to a temporary file and captures output of body in ident
+  let
+    # Duplicate stdout
+    stdoutFileno = stdout.getFileHandle()
+    stdoutDupfd = dup(stdoutFileno)
+    # Create a new temporary file
+    (tmpFile, tmpFilename) = mkstemp(mode=fmWrite)
+    tmpFileFd: FileHandle = tmpFile.getFileHandle()  
+  discard dup2(tmpFileFd, stdoutFileno)  # writing to stdoutFileno now writes to tmpFile
+
+  body
+  flushFile stdout
+
+  # before reading tmpFile, flush and close
+  tmpFile.flushFile()  
+  tmpFile.close()
+  ident = readFile(tmpFileName)
+  # Restore stdout
+  discard dup2(stdoutDupfd, stdoutFileno)