Turn some potentially dangerous templates into functions

Be careful when creating templates. If the input parameters are
referenced within the body multiple times, this may lead to multiple
evaluations of functions with side-effects.

json_rpc/jsonmarshal.nim

@@ -1,9 +1,9 @@
 import macros, json, options, typetraits
 
-template expect*(actual, expected: JsonNodeKind, argName: string) =
+proc expect*(actual, expected: JsonNodeKind, argName: string) =
   if actual != expected: raise newException(ValueError, "Parameter [" & argName & "] expected " & $expected & " but got " & $actual)
 
-template expectType*(actual: JsonNodeKind, expected: typedesc, argName: string, allowNull = false) =
+proc expectType*(actual: JsonNodeKind, expected: typedesc, argName: string, allowNull = false) =
   var expType: JsonNodeKind
   when expected is array:
     expType = JArray

json_rpc/router.nim

@@ -59,7 +59,7 @@ proc clear*(router: var RpcRouter) = router.procs.clear
 
 proc hasMethod*(router: RpcRouter, methodName: string): bool = router.procs.hasKey(methodName)
 
-template isEmpty(node: JsonNode): bool = node.isNil or node.kind == JNull
+func isEmpty(node: JsonNode): bool = node.isNil or node.kind == JNull
 
 # Json state checking
 

tests/ethhexstrings.nim

@@ -15,12 +15,14 @@ proc encodeQuantity*(value: SomeUnsignedInt): string =
   var hValue = value.toHex.stripLeadingZeros
   result = "0x" & hValue
 
-template hasHexHeader*(value: string | HexDataStr | HexQuantityStr): bool =
-  template strVal: untyped = value.string
+func hasHexHeader*(value: string): bool =
   if strVal != "" and strVal[0] == '0' and strVal[1] in {'x', 'X'} and strVal.len > 2: true
   else: false
 
-template isHexChar*(c: char): bool =
+template hasHexHeader*(value: HexDataStr|HexQuantityStr): bool =
+  value.string.hasHexHeader
+
+func isHexChar*(c: char): bool =
   if  c notin {'0'..'9'} and
       c notin {'a'..'f'} and
       c notin {'A'..'F'}: false