diff options
Diffstat (limited to 'lib/stdlib/doc/src/ets.xml')
| -rw-r--r-- | lib/stdlib/doc/src/ets.xml | 269 |
1 files changed, 98 insertions, 171 deletions
diff --git a/lib/stdlib/doc/src/ets.xml b/lib/stdlib/doc/src/ets.xml index 746f94d3f4..efd9514db6 100644 --- a/lib/stdlib/doc/src/ets.xml +++ b/lib/stdlib/doc/src/ets.xml @@ -4,7 +4,7 @@ <erlref> <header> <copyright> - <year>1996</year><year>2010</year> + <year>1996</year><year>2011</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> @@ -126,15 +126,30 @@ <em>ERTS User's Guide</em>.</p> </section> - <section> - <title>DATA TYPES</title> - <code type="none"> -match_spec() - a match specification, see above - -tid() - a table identifier, as returned by new/2</code> - </section> + <datatypes> + <datatype> + <name><marker id="type-continuation">continuation()</marker></name> + <desc> + <p>Opaque continuation used by <seealso marker="#select/1"> + <c>select/1</c></seealso> and <seealso marker="#select/3"> + <c>select/3</c></seealso>.</p> + </desc> + </datatype> + <datatype> + <name name="match_spec"/> + <desc><p>A match specification, see above.</p></desc> + </datatype> + <datatype> + <name name="match_pattern"/> + </datatype> + <datatype> + <name name="tab"/> + </datatype> + <datatype> + <name name="tid"/> + <desc><p>A table identifier, as returned by new/2.</p></desc> + </datatype> + </datatypes> <funcs> <func> <name>all() -> [Tab]</name> @@ -197,37 +212,25 @@ tid() </desc> </func> <func> - <name>file2tab(Filename) -> {ok,Tab} | {error,Reason}</name> + <name name="file2tab" arity="1"/> <fsummary>Read an ETS table from a file.</fsummary> - <type> - <v>Filename = string() | atom()</v> - <v>Tab = tid() | atom()</v> - <v>Reason = term()</v> - </type> <desc> <p>Reads a file produced by <seealso marker="#tab2file/2">tab2file/2</seealso> or <seealso marker="#tab2file/3">tab2file/3</seealso> and creates the - corresponding table <c>Tab</c>.</p> - <p>Equivalent to <c>file2tab(Filename,[])</c>.</p> + corresponding table <c><anno>Tab</anno></c>.</p> + <p>Equivalent to <c>file2tab(<anno>Filename</anno>, [])</c>.</p> </desc> </func> <func> - <name>file2tab(Filename,Options) -> {ok,Tab} | {error,Reason}</name> + <name name="file2tab" arity="2"/> <fsummary>Read an ETS table from a file.</fsummary> - <type> - <v>Filename = string() | atom()</v> - <v>Tab = tid() | atom()</v> - <v>Options = [Option]</v> - <v>Option = {verify, bool()}</v> - <v>Reason = term()</v> - </type> <desc> <p>Reads a file produced by <seealso marker="#tab2file/2">tab2file/2</seealso> or <seealso marker="#tab2file/3">tab2file/3</seealso> and creates the - corresponding table <c>Tab</c>.</p> - <p>The currently only supported option is <c>{verify,bool()}</c>. If + corresponding table <c><anno>Tab</anno></c>.</p> + <p>The currently only supported option is <c>{verify,boolean()}</c>. If verification is turned on (by means of specifying <c>{verify,true}</c>), the function utilizes whatever information is present in the file to assert that the @@ -271,70 +274,52 @@ tid() </desc> </func> <func> - <name>foldl(Function, Acc0, Tab) -> Acc1</name> + <name name="foldl" arity="3"/> <fsummary>Fold a function over an ETS table</fsummary> - <type> - <v>Function = fun(A, AccIn) -> AccOut</v> - <v>Tab = tid() | atom()</v> - <v>Acc0 = Acc1 = AccIn = AccOut = term()</v> - </type> <desc> - <p><c>Acc0</c> is returned if the table is empty. + <p><c><anno>Acc0</anno></c> is returned if the table is empty. This function is similar to <c>lists:foldl/3</c>. The order in which the elements of the table are traversed is unspecified, except for tables of type <c>ordered_set</c>, for which they are traversed first to last.</p> - <p>If <c>Function</c> inserts objects into the table, or another + <p>If <c><anno>Function</anno></c> inserts objects into the table, or another process inserts objects into the table, those objects <em>may</em> (depending on key ordering) be included in the traversal.</p> </desc> </func> <func> - <name>foldr(Function, Acc0, Tab) -> Acc1</name> + <name name="foldr" arity="3"/> <fsummary>Fold a function over an ETS table</fsummary> - <type> - <v>Function = fun(A, AccIn) -> AccOut</v> - <v>Tab = tid() | atom()</v> - <v>Acc0 = Acc1 = AccIn = AccOut = term()</v> - </type> <desc> - <p><c>Acc0</c> is returned if the table is empty. + <p><c><anno>Acc0</anno></c> is returned if the table is empty. This function is similar to <c>lists:foldr/3</c>. The order in which the elements of the table are traversed is unspecified, except for tables of type <c>ordered_set</c>, for which they are traversed last to first.</p> - <p>If <c>Function</c> inserts objects into the table, or another + <p>If <c><anno>Function</anno></c> inserts objects into the table, or another process inserts objects into the table, those objects <em>may</em> (depending on key ordering) be included in the traversal.</p> </desc> </func> <func> - <name>from_dets(Tab, DetsTab) -> true</name> + <name name="from_dets" arity="2"/> <fsummary>Fill an ETS table with objects from a Dets table.</fsummary> - <type> - <v>Tab = tid() | atom()</v> - <v>DetsTab = atom()</v> - </type> <desc> <p>Fills an already created ETS table with the objects in the - already opened Dets table named <c>DetsTab</c>. The existing + already opened Dets table named <c><anno>DetsTab</anno></c>. The existing objects of the ETS table are kept unless overwritten.</p> <p>Throws a badarg error if any of the tables does not exist or the dets table is not open.</p> </desc> </func> <func> - <name>fun2ms(LiteralFun) -> MatchSpec</name> + <name name="fun2ms" arity="1"/> <fsummary>Pseudo function that transforms fun syntax to a match_spec.</fsummary> - <type> - <v>LiteralFun -- see below</v> - <v>MatchSpec = match_spec()</v> - </type> <desc> <p>Pseudo function that by means of a <c>parse_transform</c> - translates <c>LiteralFun</c> typed as parameter in the + translates <c><anno>LiteralFun</anno></c> typed as parameter in the function call to a <seealso marker="#match_spec">match_spec</seealso>. With "literal" is meant that the fun needs to textually be written @@ -342,7 +327,7 @@ tid() variable which in turn is passed to the function).</p> <p>The parse transform is implemented in the module <c>ms_transform</c> and the source <em>must</em> include the - file <c>ms_transform.hrl</c> in <c>stdlib</c> for this + file <c>ms_transform.hrl</c> in STDLIB for this pseudo function to work. Failing to include the hrl file in the source will result in a runtime error, not a compile time ditto. The include file is easiest included by adding @@ -422,20 +407,17 @@ Error: fun containing local Erlang function calls </desc> </func> <func> - <name>i() -> ok</name> + <name name="i" arity="0"/> <fsummary>Display information about all ETS tables on tty.</fsummary> <desc> <p>Displays information about all ETS tables on tty.</p> </desc> </func> <func> - <name>i(Tab) -> ok</name> + <name name="i" arity="1"/> <fsummary>Browse an ETS table on tty.</fsummary> - <type> - <v>Tab = tid() | atom()</v> - </type> <desc> - <p>Browses the table <c>Tab</c> on tty.</p> + <p>Browses the table <c><anno>Tab</anno></c> on tty.</p> </desc> </func> <func> @@ -454,7 +436,7 @@ Error: fun containing local Erlang function calls correct type, this function fails with reason <c>badarg</c>.</p> <list type="bulleted"> - <item><c>Item=memory, Value=int()</c> <br></br> + <item><c>Item=memory, Value=integer()</c> <br></br> The number of words allocated to the table.</item> <item><c>Item=owner, Value=pid()</c> <br></br> @@ -466,7 +448,7 @@ Error: fun containing local Erlang function calls <item><c>Item=name, Value=atom()</c> <br></br> The name of the table.</item> - <item><c>Item=size, Value=int()</c> <br></br> + <item><c>Item=size, Value=integer()</c> <br></br> The number of objects inserted in the table.</item> <item><c>Item=node, Value=atom()</c> <br></br> @@ -479,7 +461,7 @@ Error: fun containing local Erlang function calls <item><c>Item=type, Value=set|ordered_set|bag|duplicate_bag</c> <br></br> The table type.</item> - <item><c>Item=keypos, Value=int()</c> <br></br> + <item><c>Item=keypos, Value=integer()</c> <br></br> The key position.</item> <item><c>Item=protection, Value=public|protected|private</c> <br></br> @@ -530,31 +512,27 @@ Error: fun containing local Erlang function calls of the reference counter, keeping track of how many times the table has been fixed by the process.</p> <p>If the table never has been fixed, the call returns - <c>false</c>.</p> - </item> + <c>false</c>.</p></item> + <item><p><c>Item=stats, Value=tuple()</c> <br></br> + Returns internal statistics about set, bag and duplicate_bag tables on an internal format used by OTP test suites. + Not for production use.</p></item> </list> </desc> </func> <func> - <name>init_table(Name, InitFun) -> true</name> + <name name="init_table" arity="2"/> <fsummary>Replace all objects of an ETS table.</fsummary> - <type> - <v>Name = atom()</v> - <v>InitFun = fun(Arg) -> Res</v> - <v>Arg = read | close</v> - <v>Res = end_of_input | {[object()], InitFun} | term()</v> - </type> <desc> - <p>Replaces the existing objects of the table <c>Tab</c> with - objects created by calling the input function <c>InitFun</c>, + <p>Replaces the existing objects of the table <c><anno>Tab</anno></c> with + objects created by calling the input function <c><anno>InitFun</anno></c>, see below. This function is provided for compatibility with the <c>dets</c> module, it is not more efficient than filling a table by using <c>ets:insert/2</c>. </p> <p>When called with the argument <c>read</c> the function - <c>InitFun</c> is assumed to return <c>end_of_input</c> when - there is no more input, or <c>{Objects, Fun}</c>, where - <c>Objects</c> is a list of objects and <c>Fun</c> is a new + <c><anno>InitFun</anno></c> is assumed to return <c>end_of_input</c> when + there is no more input, or <c>{<anno>Objects</anno>, Fun}</c>, where + <c><anno>Objects</anno></c> is a list of objects and <c>Fun</c> is a new input function. Any other value Value is returned as an error <c>{error, {init_fun, Value}}</c>. Each input function will be called exactly once, and should an error occur, the last @@ -594,7 +572,7 @@ Error: fun containing local Erlang function calls </desc> </func> <func> - <name>insert_new(Tab, ObjectOrObjects) -> bool()</name> + <name>insert_new(Tab, ObjectOrObjects) -> boolean()</name> <fsummary>Insert an object into an ETS table if the key is not already present.</fsummary> <type> <v>Tab = tid() | atom()</v> @@ -615,7 +593,7 @@ Error: fun containing local Erlang function calls </desc> </func> <func> - <name>is_compiled_ms(Term) -> bool()</name> + <name>is_compiled_ms(Term) -> boolean()</name> <fsummary>Checks if an Erlang term is the result of ets:match_spec_compile</fsummary> <type> <v>Term = term()</v> @@ -682,9 +660,9 @@ ets:is_compiled_ms(Broken).</code> table. The difference being the same as between <c>=:=</c> and <c>==</c>. As an example, one might insert an object with the - <c>integer()</c><c>1</c> as a key in an <c>ordered_set</c> + <c>integer()</c> <c>1</c> as a key in an <c>ordered_set</c> and get the object returned as a result of doing a - <c>lookup/2</c> with the <c>float()</c><c>1.0</c> as the + <c>lookup/2</c> with the <c>float()</c> <c>1.0</c> as the key to search for.</p> <p>If the table is of type <c>set</c> or <c>ordered_set</c>, the function returns either the empty list or a list with one @@ -708,7 +686,7 @@ ets:is_compiled_ms(Broken).</code> <type> <v>Tab = tid() | atom()</v> <v>Key = term()</v> - <v>Pos = int()</v> + <v>Pos = integer()</v> <v>Elem = term() | [term()]</v> </type> <desc> @@ -802,15 +780,11 @@ ets:is_compiled_ms(Broken).</code> </desc> </func> <func> - <name>match_delete(Tab, Pattern) -> true</name> + <name name="match_delete" arity="2"/> <fsummary>Delete all objects which match a given pattern from an ETS table.</fsummary> - <type> - <v>Tab = tid() | atom()</v> - <v>Pattern = tuple()</v> - </type> <desc> - <p>Deletes all objects which match the pattern <c>Pattern</c> - from the table <c>Tab</c>. See <c>match/2</c> for a + <p>Deletes all objects which match the pattern <c><anno>Pattern</anno></c> + from the table <c><anno>Tab</anno></c>. See <c>match/2</c> for a description of patterns.</p> </desc> </func> @@ -957,8 +931,8 @@ ets:select(Table,MatchSpec),</code> <v> Option = Type | Access | named_table | {keypos,Pos} | {heir,pid(),HeirData} | {heir,none} | Tweaks</v> <v> Type = set | ordered_set | bag | duplicate_bag</v> <v> Access = public | protected | private</v> - <v> Tweaks = {write_concurrency,bool()} | {read_concurrency,bool()} | compressed</v> - <v> Pos = int()</v> + <v> Tweaks = {write_concurrency,boolean()} | {read_concurrency,boolean()} | compressed</v> + <v> Pos = integer()</v> <v> HeirData = term()</v> </type> <desc> @@ -971,7 +945,7 @@ ets:select(Table,MatchSpec),</code> table is named or not. If one or more options are left out, the default values are used. This means that not specifying any options (<c>[]</c>) is the same as specifying - <c>[set,protected,{keypos,1},{heir,none},{write_concurrency,false},{read_concurrency,false}]</c>.</p> + <c>[set, protected, {keypos,1}, {heir,none}, {write_concurrency,false}, {read_concurrency,false}]</c>.</p> <list type="bulleted"> <item> <p><c>set</c> @@ -988,7 +962,7 @@ ets:select(Table,MatchSpec),</code> <c>ordered_set</c> tables regard keys as equal when they <em>compare equal</em>, not only when they match. This means that to an <c>ordered_set</c>, the - <c>integer()</c><c>1</c> and the <c>float()</c><c>1.0</c> are regarded as equal. This also means that the + <c>integer()</c> <c>1</c> and the <c>float()</c> <c>1.0</c> are regarded as equal. This also means that the key used to lookup an element not necessarily <em>matches</em> the key in the elements returned, if <c>float()</c>'s and <c>integer()</c>'s are mixed in @@ -1050,7 +1024,7 @@ ets:select(Table,MatchSpec),</code> </item> <item> <marker id="new_2_write_concurrency"></marker> - <p><c>{write_concurrency,bool()}</c> + <p><c>{write_concurrency,boolean()}</c> Performance tuning. Default is <c>false</c>, in which case an operation that mutates (writes to) the table will obtain exclusive access, blocking any concurrent access of the same table until finished. @@ -1074,7 +1048,7 @@ ets:select(Table,MatchSpec),</code> </item> <item> <marker id="new_2_read_concurrency"></marker> - <p><c>{read_concurrency,bool()}</c> + <p><c>{read_concurrency,boolean()}</c> Performance tuning. Default is <c>false</c>. When set to <c>true</c>, the table is optimized for concurrent read operations. When this option is enabled on a runtime system with @@ -1160,12 +1134,8 @@ ets:select(Table,MatchSpec),</code> </desc> </func> <func> - <name>repair_continuation(Continuation, MatchSpec) -> Continuation</name> + <name name="repair_continuation" arity="2"/> <fsummary>Repair a continuation from ets:select/1 or ets:select/3 that has passed through external representation</fsummary> - <type> - <v>Continuation = term()</v> - <v>MatchSpec = match_spec()</v> - </type> <desc> <p>This function can be used to restore an opaque continuation returned by <c>ets:select/3</c> or <c>ets:select/1</c> if the @@ -1551,7 +1521,7 @@ is_integer(X), is_integer(Y), X + Y < 4711]]></code> <fsummary>Return all objects in a given slot of an ETS table.</fsummary> <type> <v>Tab = tid() | atom()</v> - <v>I = int()</v> + <v>I = integer()</v> <v>Object = tuple()</v> </type> <desc> @@ -1572,32 +1542,19 @@ is_integer(X), is_integer(Y), X + Y < 4711]]></code> </desc> </func> <func> - <name>tab2file(Tab, Filename) -> ok | {error,Reason}</name> + <name name="tab2file" arity="2"/> <fsummary>Dump an ETS table to a file.</fsummary> - <type> - <v>Tab = tid() | atom()</v> - <v>Filename = string() | atom()</v> - <v>Reason = term()</v> - </type> <desc> - <p>Dumps the table <c>Tab</c> to the file <c>Filename</c>.</p> - <p>Equivalent to <c>tab2file(Tab, Filename,[])</c></p> + <p>Dumps the table <c><anno>Tab</anno></c> to the file <c><anno>Filename</anno></c>.</p> + <p>Equivalent to <c>tab2file(<anno>Tab</anno>, <anno>Filename</anno>,[])</c></p> </desc> </func> <func> - <name>tab2file(Tab, Filename, Options) -> ok | {error,Reason}</name> + <name name="tab2file" arity="3"/> <fsummary>Dump an ETS table to a file.</fsummary> - <type> - <v>Tab = tid() | atom()</v> - <v>Filename = string() | atom()</v> - <v>Options = [Option]</v> - <v>Option = {extended_info, [ExtInfo]}</v> - <v>ExtInfo = object_count | md5sum</v> - <v>Reason = term()</v> - </type> <desc> - <p>Dumps the table <c>Tab</c> to the file <c>Filename</c>.</p> + <p>Dumps the table <c><anno>Tab</anno></c> to the file <c><anno>Filename</anno></c>.</p> <p>When dumping the table, certain information about the table is dumped to a header at the beginning of the dump. This information contains data about the table type, @@ -1634,26 +1591,15 @@ is_integer(X), is_integer(Y), X + Y < 4711]]></code> </desc> </func> <func> - <name>tab2list(Tab) -> [Object]</name> + <name name="tab2list" arity="1"/> <fsummary>Return a list of all objects in an ETS table.</fsummary> - <type> - <v>Tab = tid() | atom()</v> - <v>Object = tuple()</v> - </type> <desc> - <p>Returns a list of all objects in the table <c>Tab</c>.</p> + <p>Returns a list of all objects in the table <c><anno>Tab</anno></c>.</p> </desc> </func> <func> - <name>tabfile_info(Filename) -> {ok, TableInfo} | {error, Reason}</name> + <name name="tabfile_info" arity="1"/> <fsummary>Return a list of all objects in an ETS table.</fsummary> - <type> - <v>Filename = string() | atom()</v> - <v>TableInfo = [InfoItem]</v> - <v>InfoItem = {InfoTag, term()}</v> - <v>InfoTag = name | type | protection | named_table | keypos | size | extended_info | version</v> - <v>Reason = term()</v> - </type> <desc> <p>Returns information about the table dumped to file by <seealso marker="#tab2file/2">tab2file/2</seealso> or @@ -1699,7 +1645,7 @@ is_integer(X), is_integer(Y), X + Y < 4711]]></code> one or more of the atoms <c>object_count</c> and <c>md5sum</c>.</item> <tag>version</tag> - <item>A tuple <c>{Major,Minor}</c> containing the major and + <item>A tuple <c>{<anno>Major</anno>,<anno>Minor</anno>}</c> containing the major and minor version of the file format for ets table dumps. This version field was added beginning with stdlib-1.5.1, files dumped with older versions will return <c>{0,0}</c> in this @@ -1712,20 +1658,11 @@ is_integer(X), is_integer(Y), X + Y < 4711]]></code> </desc> </func> <func> - <name>table(Tab [, Options]) -> QueryHandle</name> + <name name="table" arity="1"/> + <name name="table" arity="2"/> <fsummary>Return a QLC query handle.</fsummary> - <type> - <v>Tab = tid() | atom()</v> - <v>QueryHandle = - a query handle, see qlc(3) -</v> - <v>Options = [Option] | Option</v> - <v>Option = {n_objects, NObjects} | {traverse, TraverseMethod}</v> - <v>NObjects = default | integer() > 0</v> - <v>TraverseMethod = first_next | last_prev | select | {select, MatchSpec}</v> - <v>MatchSpec = match_spec()</v> - </type> <desc> - <p> <marker id="qlc_table"></marker> -Returns a QLC (Query List + <p><marker id="qlc_table"></marker>Returns a QLC (Query List Comprehension) query handle. The module <c>qlc</c> implements a query language aimed mainly at Mnesia but ETS tables, Dets tables, and lists are also recognized by QLC as sources of @@ -1760,7 +1697,7 @@ Returns a QLC (Query List that matches all objects.</p> </item> <item> - <p><c>{select, MatchSpec}</c>. As for <c>select</c> + <p><c>{select, <anno>MatchSpec</anno>}</c>. As for <c>select</c> the table is traversed by calling <c>ets:select/3</c> and <c>ets:select/1</c>. The difference is that the match_spec is explicitly given. This is how to state @@ -1788,41 +1725,31 @@ true</pre> </desc> </func> <func> - <name>test_ms(Tuple, MatchSpec) -> {ok, Result} | {error, Errors}</name> + <name name="test_ms" arity="2"/> <fsummary>Test a match_spec for use in ets:select/2.</fsummary> - <type> - <v>Tuple = tuple()</v> - <v>MatchSpec = match_spec()</v> - <v>Result = term()</v> - <v>Errors = [{warning|error, string()}]</v> - </type> <desc> <p>This function is a utility to test a <seealso marker="#match_spec">match_spec</seealso> used in calls to <c>ets:select/2</c>. The function both tests - <c>MatchSpec</c> for "syntactic" correctness and runs the - match_spec against the object <c>Tuple</c>. If the match_spec - contains errors, the tuple <c>{error, Errors}</c> is returned - where <c>Errors</c> is a list of natural language + <c><anno>MatchSpec</anno></c> for "syntactic" correctness and runs the + match_spec against the object <c><anno>Tuple</anno></c>. If the match_spec + contains errors, the tuple <c>{error, <anno>Errors</anno>}</c> is returned + where <c><anno>Errors</anno></c> is a list of natural language descriptions of what was wrong with the match_spec. If the match_spec is syntactically OK, the function returns - <c>{ok,Term}</c> where <c>Term</c> is what would have been + <c>{ok,<anno>Result</anno>}</c> where <c><anno>Result</anno></c> is what would have been the result in a real <c>ets:select/2</c> call or <c>false</c> - if the match_spec does not match the object <c>Tuple</c>.</p> + if the match_spec does not match the object <c><anno>Tuple</anno></c>.</p> <p>This is a useful debugging and test tool, especially when writing complicated <c>ets:select/2</c> calls.</p> </desc> </func> <func> - <name>to_dets(Tab, DetsTab) -> DetsTab</name> + <name name="to_dets" arity="2"/> <fsummary>Fill a Dets table with objects from an ETS table.</fsummary> - <type> - <v>Tab = tid() | atom()</v> - <v>DetsTab = atom()</v> - </type> <desc> <p>Fills an already created/opened Dets table with the objects - in the already opened ETS table named <c>Tab</c>. The Dets + in the already opened ETS table named <c><anno>Tab</anno></c>. The Dets table is emptied before the objects are inserted.</p> </desc> </func> @@ -1835,7 +1762,7 @@ true</pre> <v>Tab = tid() | atom()</v> <v>Key = term()</v> <v>UpdateOp = {Pos,Incr} | {Pos,Incr,Threshold,SetValue}</v> - <v>Pos = Incr = Threshold = SetValue = Result = int()</v> + <v>Pos = Incr = Threshold = SetValue = Result = integer()</v> </type> <desc> <p>This function provides an efficient way to update one or more @@ -1897,7 +1824,7 @@ true</pre> <type> <v>Tab = tid() | atom()</v> <v>Key = Value = term()</v> - <v>Pos = int()</v> + <v>Pos = integer()</v> </type> <desc> <p>This function provides an efficient way to update one or more |