1 files changed, 10 insertions, 0 deletions
diff --git a/lib/pure/strtabs.nim b/lib/pure/strtabs.nim
index 2028daa50..584282fbc 100755
--- a/lib/pure/strtabs.nim
+++ b/lib/pure/strtabs.nim
@@ -92,6 +92,14 @@ proc `[]`*(t: PStringTable, key: string): string {.rtl, extern: "nstGet".} =
   if index >= 0: result = t.data[index].val
   else: result = ""
 
+proc modGet*(t: PStringTable, key: string): var string {.
+             rtl, extern: "nstTake".} =
+  ## retrieves the location at ``t[key]``. If `key` is not in `t`, the
+  ## ``EInvalidValue`` exception is raised.
+  var index = RawGet(t, key)
+  if index >= 0: result = t.data[index].val
+  else: raise newException(EInvalidValue, "key does not exist: " & key)
+
 proc hasKey*(t: PStringTable, key: string): bool {.rtl, extern: "nst$1".} =
   ## returns true iff `key` is in the table `t`.
   result = rawGet(t, key) >= 0
@@ -213,4 +221,6 @@ when isMainModule:
   assert x["k"] == "v"
   assert x["11"] == "22"
   assert x["565"] == "67"
+  x.modGet("11") = "23"
+  assert x["11"] == "23"