add slice() and splice() to arrays

diff --git a/site/cgi-bin/modules/Squirrel/Template/Expr/WrapArray.pm b/site/cgi-bin/modules/Squirrel/Template/Expr/WrapArray.pm
index ca638d3..157a2e5 100644 (file)
--- a/site/cgi-bin/modules/Squirrel/Template/Expr/WrapArray.pm
+++ b/site/cgi-bin/modules/Squirrel/Template/Expr/WrapArray.pm
@@ -4,7 +4,7 @@ use base qw(Squirrel::Template::Expr::WrapBase);
 use Scalar::Util ();
 use List::Util ();
 
-our $VERSION = "1.009";
+our $VERSION = "1.010";
 
 my $list_make_key = sub {
   my ($item, $field) = @_;
@@ -215,6 +215,38 @@ sub _do_map {
     ];
 }
 
+sub _do_slice {
+  my ($self, $args) = @_;
+
+  my @result;
+  if (@$args == 1 && Scalar::Util::reftype($args->[0]) eq "ARRAY") {
+    @result = @{$self->[0]}[@{$args->[0]}];
+  }
+  else {
+    @result = @{$self->[0]}[@$args];
+  }
+
+  return \@result;
+}
+
+sub _do_splice {
+  my ($self, $args) = @_;
+
+  @$args >= 1 && @$args <= 3
+    or die [ error => "list.splice() requires 1 to 3 parameters" ];
+  my $offset = $args->[0];
+  $offset < 0 and $offset = @{$self->[0]} + $offset;
+  my $len = @$args >= 2 ? $args->[1] : @{$self->[0]} - $offset;
+  my $replace = [];
+  if (@$args >= 3) {
+    Scalar::Util::reftype($args->[2]) eq "ARRAY"
+      or die [ error => "list.splice() third argument must be a list" ];
+    $replace = $args->[2];
+  }
+
+  return [ splice(@{$self->[0]}, $offset, $len, @$replace) ];
+}
+
 sub call {
   my ($self, $method, $args) = @_;
 
@@ -336,6 +368,40 @@ element.
 Set the specified I<index> in the array to I<value>.  Returns
 I<value>.
 
+=item splice(array_of_indexes)
+
+=item splice(index1, index2, ...)
+
+Return a selection of elements from the array as a new array specified
+by index.  The indexes can be supplied either as an array:
+
+  [ "A" .. "Z" ].slice([ 0 .. 5 ]) # first 6 elements
+
+or as separate arguments:
+
+  [ "A" .. "Z" ].slice(0, 1, -2, -1) # first 2 and last 2 elements
+
+=item splice(start)
+
+=item splice(start, count)
+
+=item splice(start, count, replace)
+
+Removes elements from an array, optionally inserting the elements in
+the I<replace> aray in their place.
+
+If I<count> is ommitted, all elements to the end of the array are
+removed.
+
+If I<replace> is omitted, the elements are simply removed.
+
+  <: .set foo = [ "A" .. "J" ] :>
+  <:= foo.splice(5).join("") :> # FGHIJ
+  <:= foo.join("") :>           # ABCDE since splice() modifies it's argument
+  <: .set bar = [ "A" .. "J" ] :>
+  <:= bar.splice(8, 2, [ "Y", "Z" ]).join("") :> # IJ
+  <:= bar.join("") :> # ABCDEFGHYZ
+
 =item as_hash
 
 Returns a hash formed as if the array was formed of key and value

diff --git a/t/020-templater/040-original.t b/t/020-templater/040-original.t
index c8bcea2..9b345f0 100644 (file)
--- a/t/020-templater/040-original.t
+++ b/t/020-templater/040-original.t
@@ -1,7 +1,7 @@
 #!perl -w
 # Basic tests for Squirrel::Template
 use strict;
-use Test::More tests => 201;
+use Test::More tests => 204;
 use HTML::Entities;
 
 sub template_test($$$$;$$);
@@ -616,6 +616,9 @@ OUT
      [ '([ "a", 1, "b", "2" ].as_hash)["a"]', 1 ],
      [ '[ 1 .. 5].grep(@{a: a mod 2 == 0 }).join(",")', '2,4' ],
      [ '[ { a: 3 }, { a: 1 }, { a: 2 } ].sort(@{a,b: b.a <=> a.a }).map(@{a: a.a}).join("")', '321' ],
+     [ '[ "A" .. "Z" ].slice([ 0 .. 5 ]).join("")', 'ABCDEF' ],
+     [ '[ "A" .. "Z" ].slice(0, 1, -2, -1).join("")', 'ABYZ' ],
+     [ '[ "A" .. "Z" ].splice(0, 5).join("")', 'ABCDE' ],
 
      # WrapHash
      [ '{ "foo": 1 }.is_list', 0 ],
@@ -776,8 +779,18 @@ template_test(<<IN, <<OUT, "array methods", \%acts, "", \%vars);
 <:.set foo = [ 1, 2, 4 ] -:>
 <:% foo.set(2, 3) -:>
 2: <:= foo[2] :>
+<:.set foo = [ "A" .. "J" ] -:>
+<:= foo.splice(8, 2, [ "Y", "Z" ]).join("") :>
+<:= foo.join("") :>
+<:.set foo = [ "A" .. "J" ] -:>
+<:= foo.splice(5).join("") :>
+<:= foo.join("") :>
 IN
 2: 3
+IJ
+ABCDEFGHYZ
+FGHIJ
+ABCDE
 OUT
 
   template_test(<<IN, <<OUT, "set undef", \%acts, "", \%vars);