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-rw-r--r--erts/doc/src/match_spec.xml54
1 files changed, 50 insertions, 4 deletions
diff --git a/erts/doc/src/match_spec.xml b/erts/doc/src/match_spec.xml
index b9f955e4db..f0390c9db8 100644
--- a/erts/doc/src/match_spec.xml
+++ b/erts/doc/src/match_spec.xml
@@ -60,7 +60,7 @@
<section>
<title>Grammar</title>
- <p>A match_spec can be described in this <em>informal</em> grammar:</p>
+ <p>A match_spec used in tracing can be described in this <em>informal</em> grammar:</p>
<list type="bulleted">
<item>MatchExpression ::= [ MatchFunction, ... ]
</item>
@@ -117,6 +117,52 @@
<c><![CDATA[display]]></c> | <c><![CDATA[caller]]></c> | <c><![CDATA[set_tcw]]></c> |
<c><![CDATA[silent]]></c></item>
</list>
+
+ <p>A match_spec used in ets can be described in this <em>informal</em> grammar:</p>
+ <list type="bulleted">
+ <item>MatchExpression ::= [ MatchFunction, ... ]
+ </item>
+ <item>MatchFunction ::= { MatchHead, MatchConditions, MatchBody }
+ </item>
+ <item>MatchHead ::= MatchVariable | <c><![CDATA['_']]></c> | { MatchHeadPart, ... }
+ </item>
+ <item>MatchHeadPart ::= term() | MatchVariable | <c><![CDATA['_']]></c></item>
+ <item>MatchVariable ::= '$&lt;number&gt;'
+ </item>
+ <item>MatchConditions ::= [ MatchCondition, ...] | <c><![CDATA[[]]]></c></item>
+ <item>MatchCondition ::= { GuardFunction } |
+ { GuardFunction, ConditionExpression, ... }
+ </item>
+ <item>BoolFunction ::= <c><![CDATA[is_atom]]></c> | <c><![CDATA[is_constant]]></c> |
+ <c><![CDATA[is_float]]></c> | <c><![CDATA[is_integer]]></c> | <c><![CDATA[is_list]]></c> |
+ <c><![CDATA[is_number]]></c> | <c><![CDATA[is_pid]]></c> | <c><![CDATA[is_port]]></c> |
+ <c><![CDATA[is_reference]]></c> | <c><![CDATA[is_tuple]]></c> | <c><![CDATA[is_binary]]></c> |
+ <c><![CDATA[is_function]]></c> | <c><![CDATA[is_record]]></c> | <c><![CDATA[is_seq_trace]]></c> |
+ <c><![CDATA['and']]></c> | <c><![CDATA['or']]></c> | <c><![CDATA['not']]></c> | <c><![CDATA['xor']]></c> |
+ <c><![CDATA[andalso]]></c> | <c><![CDATA[orelse]]></c></item>
+ <item>ConditionExpression ::= ExprMatchVariable | { GuardFunction } |
+ { GuardFunction, ConditionExpression, ... } | TermConstruct
+ </item>
+ <item>ExprMatchVariable ::= MatchVariable (bound in the MatchHead) |
+ <c><![CDATA['$_']]></c> | <c><![CDATA['$$']]></c></item>
+ <item>TermConstruct = {{}} | {{ ConditionExpression, ... }} |
+ <c><![CDATA[[]]]></c> | [ConditionExpression, ...] | NonCompositeTerm | Constant
+ </item>
+ <item>NonCompositeTerm ::= term() (not list or tuple)
+ </item>
+ <item>Constant ::= {<c><![CDATA[const]]></c>, term()}
+ </item>
+ <item>GuardFunction ::= BoolFunction | <c><![CDATA[abs]]></c> |
+ <c><![CDATA[element]]></c> | <c><![CDATA[hd]]></c> | <c><![CDATA[length]]></c> | <c><![CDATA[node]]></c> |
+ <c><![CDATA[round]]></c> | <c><![CDATA[size]]></c> | <c><![CDATA[tl]]></c> | <c><![CDATA[trunc]]></c> |
+ <c><![CDATA['+']]></c> | <c><![CDATA['-']]></c> | <c><![CDATA['*']]></c> | <c><![CDATA['div']]></c> |
+ <c><![CDATA['rem']]></c> | <c><![CDATA['band']]></c> | <c><![CDATA['bor']]></c> | <c><![CDATA['bxor']]></c> |
+ <c><![CDATA['bnot']]></c> | <c><![CDATA['bsl']]></c> | <c><![CDATA['bsr']]></c> | <c><![CDATA['>']]></c> |
+ <c><![CDATA['>=']]></c> | <c><![CDATA['<']]></c> | <c><![CDATA['=<']]></c> | <c><![CDATA['=:=']]></c> |
+ <c><![CDATA['==']]></c> | <c><![CDATA['=/=']]></c> | <c><![CDATA['/=']]></c> | <c><![CDATA[self]]></c> |
+ <c><![CDATA[get_tcw]]></c></item>
+ <item>MatchBody ::= [ ConditionExpression, ... ]</item>
+ </list>
</section>
<section>
@@ -453,8 +499,8 @@
<section>
<title>Differences between match specifications in ETS and tracing</title>
<p>ETS match specifications are there to produce a return
- value. Usually the expression contains one single
- <c><![CDATA[ActionTerm]]></c> which defines the return value without having
+ value. Usually the <c><![CDATA[MatchBody]]></c> contains one single
+ <c><![CDATA[ConditionExpression]]></c> which defines the return value without having
any side effects. Calls with side effects are not allowed in the
ETS context.</p>
<p>When tracing there is no return value to produce, the
@@ -530,7 +576,7 @@
the atom 'strider' and the tuple arity is 3 and return the whole
object.</p>
<code type="none"><![CDATA[
-[{{strider,'_'.'_'},
+[{{strider,'_','_'},
[],
['$_']}]
]]></code>