assocs: Add zip-index, zip-index-as and docs/tests.

sequences: Add map-index-as for symmetry and docs/tests.

core/assocs/assocs-docs.factor

@@ -132,7 +132,9 @@ ARTICLE: "assocs-conversions" "Associative mapping conversions"
 "Combining a sequence of assocs into a single assoc:"
 { $subsections assoc-combine }
 "Creating an assoc from key/value sequences:"
-{ $subsections zip }
+{ $subsections zip zip-as }
+"Creating an assoc from key/value sequences and their indices:"
+{ $subsections zip-index zip-index-as }
 "Creating key/value sequences from an assoc:"
 { $subsections unzip }
 ;
@@ -524,3 +526,46 @@ HELP: zip
     }
 } ;
 { unzip zip } related-words
+
+HELP: zip-as
+{ $values
+     { "keys" sequence } { "values" sequence } { "exemplar" sequence }
+     { "obj" "a sequence of key/value pairs of type " { $snippet "exemplar" } } }
+{ $description "Combines two sequences pairwise into a single sequence of key/value pairs of type " { $snippet "exemplar" } "." }
+{ $notes "Exemplar must be a sequence type; hashtables will not work yet." }
+{ $examples
+    { $example "USING: prettyprint assocs ;"
+               "{ 1 2 3 } { 4 5 6 } V{ } zip-as ."
+               "V{ { 1 4 } { 2 5 } { 3 6 } }"
+    }
+} ;
+
+HELP: zip-index
+{ $values
+    { "values" sequence }
+    { "alist" "an array of key/value pairs" }
+}
+{ $examples
+    "Zip a sequnce with its indices:"
+    { $example "USING: assocs prettyprint ;"
+        "{ 100 200 300 } zip-index ."
+        "{ { 100 0 } { 200 1 } { 300 2 } }"
+    }
+}
+{ $description "Zip a sequence with its index and return an associative list where the input sequence is the keys and the indices are the values." } ;
+
+HELP: zip-index-as
+{ $values
+    { "values" sequence } { "exemplar" sequence }
+    { "obj" "an array of key/value pairs" }
+}
+{ $examples
+    "Zip a sequnce with its indices as a vector:"
+    { $example "USING: assocs prettyprint ;"
+        "{ 100 200 300 } V{ } zip-index-as ."
+        "V{ { 100 0 } { 200 1 } { 300 2 } }"
+    }
+}
+{ $description "Zip a sequence with its index and return an associative list of type " { $snippet "exemplar" } " where the input sequence is the keys and the indices are the values." } ;
+
+{ unzip zip zip-as zip-index zip-index-as } related-words

core/assocs/assocs-tests.factor

@@ -212,3 +212,41 @@ unit-test
 } [
     { { 1 f } { f 2 } } sift-values
 ] unit-test
+
+! zip, zip-as
+{
+    { { 1 4 } { 2 5 } { 3 6 } }
+} [ { 1 2 3 } { 4 5 6 } zip ] unit-test
+
+{
+    { { 1 4 } { 2 5 } { 3 6 } }
+} [ { 1 2 3 } { 4 5 6 } { } zip-as ] unit-test
+
+{
+    { { 1 4 } { 2 5 } { 3 6 } }
+} [ B{ 1 2 3 } { 4 5 6 } { } zip-as ] unit-test
+
+{
+    V{ { 1 4 } { 2 5 } { 3 6 } }
+} [ { 1 2 3 } { 4 5 6 } V{ } zip-as ] unit-test
+
+{
+    V{ { 1 4 } { 2 5 } { 3 6 } }
+} [ BV{ 1 2 3 } BV{ 4 5 6 } V{ } zip-as ] unit-test
+
+! zip-index, zip-index-as
+{
+    { { 11 0 } { 22 1 } { 33 2 } }
+} [ { 11 22 33 } zip-index ] unit-test
+
+{
+    { { 11 0 } { 22 1 } { 33 2 } }
+} [ { 11 22 33 } { } zip-index-as ] unit-test
+
+{
+    { { 11 0 } { 22 1 } { 33 2 } }
+} [ V{ 11 22 33 } { } zip-index-as ] unit-test
+
+{
+    V{ { 11 0 } { 22 1 } { 33 2 } }
+} [ { 11 22 33 } V{ } zip-index-as ] unit-test

core/assocs/assocs.factor

@@ -198,8 +198,17 @@ M: assoc value-at* swap [ = nip ] curry assoc-find nip ;
 : push-at ( value key assoc -- )
     [ ?push ] change-at ;
 
+: zip-as ( keys values exemplar -- obj )
+    [ [ 2array ] ] dip 2map-as ; inline
+
 : zip ( keys values -- alist )
-    [ 2array ] { } 2map-as ; inline
+    { } zip-as ; inline
+
+: zip-index-as ( values exemplar -- obj )
+    [ [ 2array ] ] dip map-index-as ; inline
+
+: zip-index ( values -- alist )
+    { } zip-index-as ; inline
 
 : unzip ( assoc -- keys values )
     dup assoc-empty? [ drop { } { } ] [ >alist flip first2 ] if ;

core/sequences/sequences-docs.factor

@@ -374,6 +374,16 @@ HELP: map-index
 "{ { 10 0 } { 20 1 } { 30 2 } }"
 } } ;
 
+HELP: map-index-as
+{ $values
+  { "seq" sequence } { "quot" { $quotation ( ... elt index -- ... newelt ) } } { "exemplar" sequence } { "newseq" sequence } }
+{ $description "Calls the quotation with the element of the sequence and its index on the stack, with the index on the top of the stack. Collects the outputs of the quotation and outputs them in a sequence of the same type as the " { $snippet "exemplar" } " sequence." }
+{ $examples { $example "USING: arrays sequences prettyprint ;"
+"{ 10 20 30 } [ 2array ] V{ } map-index-as ."
+"V{ { 10 0 } { 20 1 } { 30 2 } }"
+} } ;
+{ map-index map-index-as } related-words
+
 HELP: change-nth
 { $values { "i" "a non-negative integer" } { "seq" "a mutable sequence" } { "quot" { $quotation ( ..a elt -- ..b newelt ) } } }
 { $description "Applies the quotation to the " { $snippet "i" } "th element of the sequence, storing the result back into the sequence." }
@@ -1681,6 +1691,7 @@ ARTICLE: "sequences-combinators" "Sequence combinators"
     map
     map-as
     map-index
+    map-index-as
     map-reduce
     accumulate
     accumulate-as

core/sequences/sequences-tests.factor

@@ -386,3 +386,19 @@ USE: make
 { { } } [ 0 0 <repetition> >array ] unit-test
 { { 0 } } [ 1 0 <repetition> >array ] unit-test
 { { 0 0 0 } } [ 3 0 <repetition> >array ] unit-test
+
+{
+    { 11 23 35 }
+} [ { 11 22 33 } [ + ] map-index ] unit-test
+
+{
+    V{ 11 23 35 }
+} [ { 11 22 33 } [ + ] V{ } map-index-as ] unit-test
+
+{
+    B{ 11 23 35 }
+} [ { 11 22 33 } [ + ] B{ } map-index-as ] unit-test
+
+{
+    BV{ 11 23 35 }
+} [ { 11 22 33 } [ + ] BV{ } map-index-as ] unit-test

core/sequences/sequences.factor

@@ -578,8 +578,11 @@ PRIVATE>
         3bi
     ] if ; inline
 
+: map-index-as ( ... seq quot: ( ... elt index -- ... newelt ) exemplar -- ... newseq )
+    [ dup length iota ] 2dip 2map-as ; inline
+
 : map-index ( ... seq quot: ( ... elt index -- ... newelt ) -- ... newseq )
-    [ dup length iota ] dip 2map ; inline
+    { } map-index-as ; inline
 
 : reduce-index ( ... seq identity quot: ( ... prev elt index -- ... next ) -- ... result )
     swapd each-index ; inline