erts: Document insert_element and delete_element

Document new BIFs:
* erlang:insert_element/3
* erlang:delete_element/2

2 files changed, 53 insertions, 0 deletions

diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml
index 1a97a84b42..2faa46d760 100644
--- a/erts/doc/src/erlang.xml
+++ b/erts/doc/src/erlang.xml
@@ -626,6 +626,22 @@ false</pre>
 {more,6}</pre>
       </desc>
     </func>
+
+    <func>
+      <name name="delete_element" arity="2"/>
+      <fsummary>Delete element at index in a tuple</fsummary>
+      <type_desc variable="Index">1..tuple_size(<anno>Tuple1</anno>)</type_desc>
+      <desc>
+		  <p>
+			  Returns a new tuple with element at <c><anno>Index</anno></c> removed from
+			  tuple <c><anno>Tuple1</anno></c>.
+		  </p>
+        <pre>
+> <input>erlang:delete_element(2, {one, two, three}).</input>
+{one,three}</pre>
+      </desc>
+    </func>
+
     <func>
       <name name="delete_module" arity="1"/>
       <fsummary>Make the current code for a module old</fsummary>
@@ -1361,6 +1377,24 @@ os_prompt% </pre>
           when the process wakes up.</p>
       </desc>
     </func>
+
+    <func>
+      <name name="insert_element" arity="3"/>
+      <fsummary>Insert an element at index in a tuple</fsummary>
+      <type_desc variable="Index">1..tuple_size(<anno>Tuple1</anno>) + 1</type_desc>
+      <desc>
+		  <p>
+			  Returns a new tuple with element <c><anno>Term</anno></c> insert at position
+			  <c><anno>Index</anno></c> in tuple <c><anno>Tuple1</anno></c>.
+			  All elements from position <c><anno>Index</anno></c> and upwards are subsequently
+			  pushed one step higher in the new tuple <c><anno>Tuple2</anno></c>.
+		  </p>
+        <pre>
+> <input>erlang:insert_element(2, {one, two, three}, new).</input>
+{one,new,two,three}</pre>
+      </desc>
+    </func>
+
     <func>
       <name name="integer_to_list" arity="1"/>
       <fsummary>Text representation of an integer</fsummary>
diff --git a/erts/preloaded/src/erlang.erl b/erts/preloaded/src/erlang.erl
index 51a190b095..739fdde10a 100644
--- a/erts/preloaded/src/erlang.erl
+++ b/erts/preloaded/src/erlang.erl
@@ -79,6 +79,7 @@
 -export([bump_reductions/1, byte_size/1, call_on_load_function/1]).
 -export([cancel_timer/1, check_old_code/1, check_process_code/2, crc32/1]).
 -export([crc32/2, crc32_combine/3, date/0, decode_packet/3]).
+-export([delete_element/2]).
 -export([delete_module/1, demonitor/1, demonitor/2, display/1]).
 -export([display_nl/0, display_string/1, dist_exit/3, erase/0, erase/1]).
 -export([error/1, error/2, exit/1, exit/2, external_size/1]).
@@ -88,6 +89,7 @@
 -export([garbage_collect_message_area/0, get/0, get/1, get_keys/1]).
 -export([get_module_info/1, get_stacktrace/0, group_leader/0]).
 -export([group_leader/2, halt/0, halt/1, halt/2, hash/2, hibernate/3]).
+-export([insert_element/3]).
 -export([integer_to_list/1, iolist_size/1, iolist_to_binary/1]).
 -export([is_alive/0, is_builtin/3, is_process_alive/1, length/1, link/1]).
 -export([list_to_atom/1, list_to_binary/1, list_to_bitstr/1]).
@@ -529,6 +531,14 @@ date() ->
 decode_packet(_Type, _Bin, _Options) ->
     erlang:nif_error(undefined).
 
+%% delete_element/2
+-spec erlang:delete_element(Index, Tuple1) -> Tuple2 when
+      Index  :: pos_integer(),
+      Tuple1 :: tuple(),
+      Tuple2 :: tuple().
+delete_element(_Index, _Tuple1) ->
+    erlang:nif_error(undefined).
+
 %% delete_module/1
 -spec delete_module(Module) -> true | undefined when
       Module :: module().
@@ -820,6 +830,15 @@ hash(_Term, _Range) ->
 hibernate(_Module, _Function, _Args) ->
     erlang:nif_error(undefined).
 
+%% insert_element/3
+-spec erlang:insert_element(Index, Tuple1, Term) -> Tuple2 when
+      Index  :: pos_integer(),
+      Tuple1 :: tuple(),
+      Tuple2 :: tuple(),
+      Term   :: term().
+insert_element(_Index, _Tuple1, _Term) ->
+    erlang:nif_error(undefined).
+
 %% integer_to_list/1
 -spec integer_to_list(Integer) -> string() when
       Integer :: integer().