diff --git a/src/expect-core b/src/expect-core
index 368c5be..b2d2f49 100644
--- a/src/expect-core
+++ b/src/expect-core
@@ -22,10 +22,7 @@
 [ -z $__INC_EXPECT_CORE ] || return
 __INC_EXPECT_CORE=1
 
-source util
-
-# reserved for our uses
-exec 99<>/dev/null
+source expect/output
 
 
 ##
@@ -69,125 +66,3 @@ _expect--be() { _proxy-to "$@"; }
 _expect--succeed() { test "$1" -eq 0; }
 _expect--fail()    { test "$1" -ne 0; }
 
-
-##
-# Expect that the given string is output on stdout or stderr
-#
-# Defaults to asserting against stdout; behavior may be overridden with the
-# `on stderr' clause. Specifying `on stdout' may be used for clarity, but is
-# redundant.
-#
-# This expectation assumes a trailing newline by default; this behavior can
-# be suppressed with the `without newline' clause.
-_expect--output()
-{
-  local -a args=("$@")
-  local -i shiftn="$2"
-  shift "$shiftn"
-  local -r cmp="$1"
-  shift
-  local nl
-
-  if [ $# -gt 0 ]; then
-    # this is not a common clause; process before generic parsing
-    if [ "$1 $2" == 'without newline' ]; then
-      nl=-n
-      unset args[$shiftn+1], args[$shiftn+2]
-    fi
-  fi
-
-  __expect--output-cmd "__expect--output-do -$nl" "${args[@]}"
-}
-
-__expect--output-do()
-{
-  local -r nl="${1:1}"
-  local -r cmp="$2"
-
-  # we will eventually be interested in this output
-  # TODO: fast check first, diff if non-match
-  diff <( echo $nl "$cmp" ) -
-}
-
-__expect--output-cmd()
-{
-  local -r cmd="$1"
-  shift
-
-  local -ri shiftn="$2"
-  local -r stderr="$3"
-  shift "$shiftn"
-
-  # output-specific clauses
-  local -r cmp="$1"
-  shift
-  local -ar clause=("$@")
-
-  local nl
-  local intype
-  {
-    __expect--output-clause "${clause[@]}" | {
-      IFS=\| read nl intype
-
-      if [ "$intype" == stderr ]; then
-        __chk-shiftn 3 "$shiftn"
-        exec 99<"$stderr"
-      fi
-
-      $cmd "$cmp" <&99 &>/dev/null
-    }
-  } 99<&0
-
-  aok "${PIPESTATUS[@]}"
-}
-
-# parses output remainder clause according to the aforementioned rules
-__expect--output-clause()
-{
-  [ $# -gt 0 ] || return 0
-
-  local input=
-
-  if [ $# -gt 0 ]; then
-    if [[ "$1 $2" =~ ^on\ std(err|out) ]]; then
-      [ "$2" == stderr ] && input="$2"
-    else
-      _bail_clause output "$*"
-    fi
-  fi
-
-  echo "$nl|$input"
-}
-
-
-##
-# Expects that stdout matches the provided extended regular expression (as
-# in regex(3))
-_expect--match()
-{
-  __expect--output-cmd '__expect--match-do' "$@"
-}
-
-__expect--match-do()
-{
-  local -r pat="$1"
-  [[ "$(cat)" =~ $pat ]]
-}
-
-
-##
-# Expects that both stdin and stderr (if available) are empty
-_expect--silent()
-{
-  local -r stderr="${3:-/dev/null}"
-  shift "$2"
-
-  # we accept no arguments
-  test $# -eq 0 || _bail_clause silent "$*"
-
-  # quick read using builtins; if we find any single byte, then we know that
-  # it is non-empty
-  read -N1 || read -N1 <"$stderr" || return 0
-  return 1
-}
-
diff --git a/src/expect/output b/src/expect/output
new file mode 100644
index 0000000..58164c5
--- /dev/null
+++ b/src/expect/output
@@ -0,0 +1,168 @@
+#!/bin/bash
+# Output expectations
+#
+#  Copyright (C) 2014 Mike Gewitz
+#
+#  This file is part of shspec.
+#
+#  shspec is free software: you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation, either version 3 of the License, or
+#  (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+##
+
+[ -z $__INC_EXPECT_OUTPUT ] || return
+__INC_EXPECT_OUTPUT=1
+
+source util
+
+# reserved for our uses
+exec 99<>/dev/null
+
+
+##
+# Generic output expectation processing
+#
+# This provides a generic facility for processing output on stdout or
+# stderr, supporting `on std(err|out)' clauses.
+#
+# First processes remainder clause for common sub-clauses; any
+# expectation-specific sub-clauses should therefore be processed and
+# stripped beforehand to prevent errors.
+#
+# Assuming clause validity, determines (based on the clause) whether to
+# assert against stdout or stderr, and then invokes the provided command
+# line with an additional parameter representing the user-supplied
+# comparison argument; stdout/stderr input is provided via stdin.
+#
+# This command is successful if and only if both the remainder clause and
+# the provided command line complete successfully.
+__expect-output-cmd()
+{
+  local -r cmd="$1"
+  shift
+
+  local -ri shiftn="$2"
+  local -r stderr="$3"
+  shift "$shiftn"
+
+  # output-specific clauses
+  local -r cmp="$1"
+  shift
+  local -ar clause=("$@")
+
+  local nl
+  local intype
+  {
+    __expect-output-clause "${clause[@]}" | {
+      IFS=\| read nl intype
+
+      if [ "$intype" == stderr ]; then
+        __chk-shiftn 3 "$shiftn"
+        exec 99<"$stderr"
+      fi
+
+      $cmd "$cmp" <&99 &>/dev/null
+    }
+  } 99<&0
+
+  aok "${PIPESTATUS[@]}"
+}
+
+# parses output remainder clause according to the aforementioned rules
+__expect-output-clause()
+{
+  [ $# -gt 0 ] || return 0
+
+  local input=
+
+  if [ $# -gt 0 ]; then
+    if [[ "$1 $2" =~ ^on\ std(err|out) ]]; then
+      [ "$2" == stderr ] && input="$2"
+    else
+      _bail_clause output "$*"
+    fi
+  fi
+
+  echo "$nl|$input"
+}
+
+
+##
+# Expect that the given string is output on stdout or stderr
+#
+# Defaults to asserting against stdout; behavior may be overridden with the
+# `on stderr' clause. Specifying `on stdout' may be used for clarity, but is
+# redundant.
+#
+# This expectation assumes a trailing newline by default; this behavior can
+# be suppressed with the `without newline' clause.
+_expect--output()
+{
+  local -a args=("$@")
+  local -i shiftn="$2"
+  shift "$shiftn"
+  local -r cmp="$1"
+  shift
+  local nl
+
+  if [ $# -gt 0 ]; then
+    # this is not a common clause; process before generic parsing
+    if [ "$1 $2" == 'without newline' ]; then
+      nl=-n
+      unset args[$shiftn+1], args[$shiftn+2]
+    fi
+  fi
+
+  __expect-output-cmd "__expect--output-do -$nl" "${args[@]}"
+}
+
+__expect--output-do()
+{
+  local -r nl="${1:1}"
+  local -r cmp="$2"
+
+  # we will eventually be interested in this output
+  # TODO: fast check first, diff if non-match
+  diff <( echo $nl "$cmp" ) -
+}
+
+
+##
+# Expects that stdout matches the provided extended regular expression (as
+# in regex(3))
+_expect--match()
+{
+  __expect-output-cmd '__expect--match-do' "$@"
+}
+
+__expect--match-do()
+{
+  local -r pat="$1"
+  [[ "$(cat)" =~ $pat ]]
+}
+
+
+##
+# Expects that both stdin and stderr (if available) are empty
+_expect--silent()
+{
+  local -r stderr="${3:-/dev/null}"
+  shift "$2"
+
+  # we accept no arguments
+  test $# -eq 0 || _bail_clause silent "$*"
+
+  # quick read using builtins; if we find any single byte, then we know that
+  # it is non-empty
+  read -N1 || read -N1 <"$stderr" || return 0
+  return 1
+}