diff --git a/src/macLib/EPICS/macLib.pm b/src/macLib/EPICS/macLib.pm
new file mode 100644
index 000000000..412c6d709
--- /dev/null
+++ b/src/macLib/EPICS/macLib.pm
@@ -0,0 +1,250 @@
+#*************************************************************************
+# Copyright (c) 2010 UChicago Argonne LLC, as Operator of Argonne
+#     National Laboratory.
+# EPICS BASE is distributed subject to a Software License Agreement found
+# in file LICENSE that is included with this distribution.
+#*************************************************************************
+
+package EPICS::macLib::entry;
+
+sub new ($$) {
+    my $class = shift;
+    my $this = {
+        name => shift,
+        type => shift,
+        raw => '',
+        val => '',
+        visited => 0,
+        error => 0,
+    };
+    bless $this, $class;
+    return $this;
+}
+
+sub report ($) {
+    my ($this) = @_;
+    return unless defined $this->{raw};
+    printf "%1s %-16s %-16s %s\n",
+        ($this->{error} ? '*' : ' '), $this->{name}, $this->{raw}, $this->{val};
+}
+
+
+package EPICS::macLib;
+
+use Carp;
+
+sub new ($@) {
+    my $proto = shift;
+    my $class = ref($proto) || $proto;
+    my $this = {
+        dirty => 0,
+        noWarn => 0,
+        macros => [{}], # [0] is current scope, [1] is parent etc.
+    };
+    bless $this, $class;
+    $this->installList(@_);
+    return $this;
+}
+
+sub installList ($@) {
+    # Argument is a list of strings which are arguments to installMacros
+    my $this = shift;
+    while (@_) {
+        $this->installMacros(shift);
+    }
+}
+
+sub installMacros ($$) {
+    # Argument is a string: a=1,b="2",c,d='hello'
+    my $this = shift;
+    $_ = shift;
+    until (defined pos($_) and pos($_) == length($_)) {
+        m/\G \s* /xgc;    # Skip whitespace
+        if (m/\G ( [A-Za-z0-9_-]+ ) \s* /xgc) {
+            my ($name, $val) = ($1);
+            if (m/\G = \s* /xgc) {
+                # The value follows, handle quotes and escapes
+                until (pos($_) == length($_)) {
+                    if (m/\G , /xgc) { last; }
+                    elsif (m/\G ' ( ( [^'] | \\ ' )* ) ' /xgc) { $val .= $1; }
+                    elsif (m/\G " ( ( [^"] | \\ " )* ) " /xgc) { $val .= $1; }
+                    elsif (m/\G \\ ( . ) /xgc) { $val .= $1; }
+                    elsif (m/\G ( . ) /xgc) { $val .= $1; }
+                    else { die "How did I get here?"; }
+                }
+                $this->putValue($name, $val);
+            } elsif (m/\G , /xgc or (pos($_) == length($_))) {
+                $this->putValue($name, undef);
+            } else {
+                warn "How did I get here?";
+            }
+        } elsif (m/\G ( .* )/xgc) {
+            croak "Can't find a macro definition in '$1'";
+        } else {
+            last;
+        }
+    }
+}
+
+sub putValue ($$$) {
+    my ($this, $name, $raw) = @_;
+    if (exists $this->{macros}[0]{$name}) {
+        if (!defined $raw) {
+            delete $this->{macros}[0]{$name};
+        } else {
+            $this->{macros}[0]{$name}{raw} = $raw;
+        }
+    } else {
+        my $entry = EPICS::macLib::entry->new($name, 'macro');
+        $entry->{raw} = $raw;
+        $this->{macros}[0]{$name} = $entry;
+    }
+    $this->{dirty} = 1;
+}
+
+sub pushScope ($) {
+    my ($this) = @_;
+    unshift @{$this->{macros}}, {};
+}
+
+sub popScope ($) {
+    my ($this) = @_;
+    shift @{$this->{macros}};
+}
+
+sub suppressWarning($$) {
+    my ($this, $suppress) = @_;
+    $this->{noWarn} = $suppress;
+}
+
+sub expandString($$) {
+    my ($this, $src) = @_;
+    $this->_expand;
+    (my $name = $src) =~ s/^ (.{20}) .* $/$1.../xs;
+    my $entry = EPICS::macLib::entry->new($name, 'string');
+    my $result = $this->_translate($entry, 0, $src);
+    return $result unless $entry->{error};
+    return $this->{noWarn} ? $result : undef;
+}
+
+sub reportMacros ($) {
+    my ($this) = @_;
+    $this->_expand;
+    print "Macro report\n============\n";
+    foreach my $scope (@{$this->{macros}}) {
+        foreach my $name (keys %{$scope}) {
+            my $entry = $scope->{$name};
+            $entry->report;
+        }
+    } continue {
+        print " -- scope ends --\n";
+    }
+}
+
+
+# Private routines, not intended for public use
+
+sub _expand ($) {
+    my ($this) = @_;
+    return unless $this->{dirty};
+    foreach my $scope (@{$this->{macros}}) {
+        foreach my $name (keys %{$scope}) {
+            my $entry = $scope->{$name};
+            $entry->{val} = $this->_translate($entry, 1, $entry->{raw});
+        }
+    }
+    $this->{dirty} = 0;
+}
+
+sub _lookup ($$$$$) {
+    my ($this, $name) = @_;
+    foreach my $scope (@{$this->{macros}}) {
+        if (exists $scope->{$name}) {
+            return undef   # Macro marked as deleted
+                unless defined $scope->{$name}{raw};
+            return $scope->{$name};
+        }
+    }
+    return undef;
+}
+
+sub _translate ($$$$) {
+    my ($this, $entry, $level, $str) = @_;
+    return $this->_trans($entry, $level, '', \$str);
+}
+
+sub _trans ($$$$$) {
+    my ($this, $entry, $level, $term, $R) = @_;
+    return $$R
+        if (!defined $$R or
+            $$R =~ m/\A [^\$]* \Z/x);   # Short-circuit if no macros
+    my $quote = 0;
+    my $val;
+    until (defined pos($$R) and pos($$R) == length($$R)) {
+        if ($term and ($$R =~ m/\G (?= [$term] ) /xgc)) {
+            last;
+        }
+        if ($$R =~ m/\G \$ ( [({] ) /xgc) {
+            my $macEnd = $1;
+            $macEnd =~ tr/({/)}/;
+            my $name2 = $this->_trans($entry, $level+1, "=$macEnd", $R);
+            my $entry2 = $this->_lookup($name2);
+            if (!defined $entry2) {             # Macro not found
+                if ($$R =~ m/\G = /xgc) {       # Use default value given
+                    $val .= $this->_trans($entry, $level+1, $macEnd, $R);
+                } else {
+                    unless ($this->{noWarn}) {
+                        $entry->{error} = 1;
+                        printf STDERR "macLib: macro '%s' is undefined (expanding %s '%s')\n",
+                            $name2, $entry->{type}, $entry->{name};
+                    }
+                    $val .= "\$($name2)";
+                }
+                $$R =~ m/\G [$macEnd] /xgc;     # Discard close bracket
+            } else {                            # Macro found
+                if ($entry2->{visited}) {
+                    $entry->{error} = 1;
+                    printf STDERR "macLib: %s '%s' is recursive (expanding %s '%s')\n",
+                        $entry->{type}, $entry->{name}, $entry2->{type}, $entry2->{name};
+                    $val .= "\$($name)";
+                } else {
+                    if ($$R =~ m/\G = /xgc) {   # Discard default value
+                        local $this->{noWarn} = 1; # Temporarily kill warnings
+                        $this->_trans($entry, $level+1, $macEnd, $R);
+                    }
+                    $$R =~ m/\G [$macEnd] /xgc; # Discard close bracket
+                    if ($this->{dirty}) {       # Translate raw value
+                        $entry2->{visited} = 1;
+                        $val .= $this->_trans($entry, $level+1, '', \$entry2->{raw});
+                        $entry2->{visited} = 0;
+                    } else {
+                        $val .= $entry2->{val}; # Here's one I made earlier...
+                    }
+                }
+            }
+        } elsif ($level > 0) {  # Discard quotes and escapes
+            if ($quote and $$R =~ m/\G $quote /xgc) {
+                $quote = 0;
+            } elsif ($$R =~ m/\G ( ['"] ) /xgc) {
+                $quote = $1;
+            } elsif ($$R =~ m/\G \\? ( . ) /xgc) {
+                $val .= $1;
+            } else {
+                warn "How did I get here? level=$level";
+            }
+        } else {                # Level 0
+            if ($$R =~ m/\G \\ ( . ) /xgc) {
+                $val .= "\\$1";
+            } elsif ($$R =~ m/\G ( [^\\\$'")}]* ) /xgc) {
+                $val .= $1;
+            } elsif ($$R =~ m/\G ( . ) /xgc) {
+                $val .= $1;
+            } else {
+                warn "How did I get here? level=$level";
+            }
+        }
+    }
+    return $val;
+}
+
+1;
diff --git a/src/macLib/Makefile b/src/macLib/Makefile
index c0be82af8..08c47bd40 100644
--- a/src/macLib/Makefile
+++ b/src/macLib/Makefile
@@ -12,3 +12,5 @@ INC += macLib.h
 Com_SRCS += macCore.c
 Com_SRCS += macEnv.c
 Com_SRCS += macUtil.c
+
+PERL_MODULES += EPICS/macLib.pm
diff --git a/test/Makefile b/test/Makefile
index fcdcce39a..9514918cf 100755
--- a/test/Makefile
+++ b/test/Makefile
@@ -187,6 +187,9 @@ macLibTest_SRCS += macLibTest.c
 testHarness_SRCS += macLibTest.c
 TESTS += macLibTest
 
+# Perl module tests:
+TESTS += macLib
+
 TESTPROD_HOST += taskwdTest
 taskwdTest_SRCS += taskwdTest.c
 testHarness_SRCS += taskwdTest.c
diff --git a/test/macLib.plt b/test/macLib.plt
new file mode 100644
index 000000000..559f27df8
--- /dev/null
+++ b/test/macLib.plt
@@ -0,0 +1,79 @@
+#!/usr/bin/perl
+
+use lib '@TOP@/lib/perl';
+
+use Test::More tests => 35;
+
+use EPICS::macLib;
+
+use Data::Dumper;
+
+my $m = EPICS::macLib->new;
+isa_ok $m, 'EPICS::macLib';
+is $m->expandString(''), '', 'Empty string';
+
+{
+    local *STDERR;
+    my $output;
+    open STDERR, '>', \$output;
+    is $m->expandString('$(undef)'), undef, 'Warning $(undef)';
+    chomp $output;
+    is $output, q/macLib: macro 'undef' is undefined (expanding string '$(undef)')/, 'macLib error message';
+}
+
+$m->suppressWarning(1);
+is $m->expandString('$(undef)'), '$(undef)', 'Suppressed $(undef)';
+
+$m->putValue('a', 'foo');
+is $m->expandString('$(a)'), 'foo', '$(a)';
+is $m->expandString('${a}'), 'foo', '${a}';
+is $m->expandString('$(a=bar)'), 'foo', '$(a=bar)';
+is $m->expandString('${a=bar}'), 'foo', '${a=bar}';
+is $m->expandString('$(undef)'), '$(undef)', '$(undef) again';
+is $m->expandString('${undef}'), '$(undef)', '${undef} again';
+
+$m->suppressWarning(0);
+is $m->expandString('$(undef=$(a))'), 'foo', '$(undef=$(a))';
+is $m->expandString('${undef=${a}}'), 'foo', '${undef=${a}}';
+is $m->expandString('${undef=$(a)}'), 'foo', '${undef=$(a)}';
+is $m->expandString('$(undef=${a})'), 'foo', '$(undef=${a})';
+is $m->expandString('$(a=$(undef))'), 'foo', '$(a=$(undef))';
+
+$m->putValue('b', 'baz');
+is $m->expandString('$(b)'), 'baz', '$(b)';
+is $m->expandString('$(a)'), 'foo', '$(a)';
+is $m->expandString('$(a)$(b)'), 'foobaz', '$(a)$(b)';
+is $m->expandString('$(a)/$(b)'), 'foo/baz', '$(a)/$(b)';
+is $m->expandString('$(a)\$(b)'), 'foo\$(b)', '$(a)\$(b)';
+is $m->expandString('$(a)$$(b)'), 'foo$baz', '$(a)$$(b)';
+
+$m->putValue('c', '$(a)');
+is $m->expandString('$(c)'), 'foo', '$(c)';
+is $m->expandString('$(undef=$(c))'), 'foo', '$(undef=$(c))';
+
+$m->putValue('d', 'c');
+is $m->expandString('$(d)'), 'c', '$(d)';
+is $m->expandString('$($(d))'), 'foo', '$($(d))';
+is $m->expandString('$($(b)=$(a))'), 'foo', '$($(b)=$(a))';
+
+$m->suppressWarning(1);
+$m->putValue('c', undef);
+is $m->expandString('$(c)'), '$(c)', '$(c) deleted';
+
+$m->installMacros('c=fum,d');
+is $m->expandString('$(c)'), 'fum', 'installMacros, $(c)';
+
+is $m->expandString('$(d)'), '$(d)', 'installMacros deletion';
+
+$m->pushScope;
+is $m->expandString('$(a)'), 'foo', 'pushScope, $(a)';
+$m->putValue('a', 'grinch');
+is $m->expandString('$(a)'), 'grinch', 'new $(a) in child';
+
+$m->putValue('b', undef);
+is $m->expandString('$(b)'), '$(b)', '$(b) deleted in child';
+
+$m->popScope;
+is $m->expandString('$(a)'), 'foo', 'popScope, $(a) restored';
+is $m->expandString('$(b)'), 'baz', '$(b) restored';
+