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-rw-r--r--erts/doc/src/absform.xml579
1 files changed, 288 insertions, 291 deletions
diff --git a/erts/doc/src/absform.xml b/erts/doc/src/absform.xml
index 8584898a9d..ca06794a53 100644
--- a/erts/doc/src/absform.xml
+++ b/erts/doc/src/absform.xml
@@ -11,7 +11,7 @@
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
-
+
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
@@ -19,7 +19,7 @@
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
-
+
</legalnotice>
<title>The Abstract Format</title>
@@ -35,24 +35,24 @@
<p></p>
<p>This document describes the standard representation of parse trees for Erlang
programs as Erlang terms. This representation is known as the <em>abstract format</em>.
- Functions dealing with such parse trees are <c><![CDATA[compile:forms/[1,2]]]></c>
+ Functions dealing with such parse trees are <c>compile:forms/[1,2]</c>
and functions in the modules
- <c><![CDATA[epp]]></c>,
- <c><![CDATA[erl_eval]]></c>,
- <c><![CDATA[erl_lint]]></c>,
- <c><![CDATA[erl_pp]]></c>,
- <c><![CDATA[erl_parse]]></c>,
+ <c>epp</c>,
+ <c>erl_eval</c>,
+ <c>erl_lint</c>,
+ <c>erl_pp</c>,
+ <c>erl_parse</c>,
and
- <c><![CDATA[io]]></c>.
+ <c>io</c>.
They are also used as input and output for parse transforms (see the module
- <c><![CDATA[compile]]></c>).</p>
- <p>We use the function <c><![CDATA[Rep]]></c> to denote the mapping from an Erlang source
- construct <c><![CDATA[C]]></c> to its abstract format representation <c><![CDATA[R]]></c>, and write
- <c><![CDATA[R = Rep(C)]]></c>.
+ <c>compile</c>).</p>
+ <p>We use the function <c>Rep</c> to denote the mapping from an Erlang source
+ construct <c>C</c> to its abstract format representation <c>R</c>, and write
+ <c>R = Rep(C)</c>.
</p>
- <p>The word <c><![CDATA[LINE]]></c> below represents an integer, and denotes the
+ <p>The word <c>LINE</c> below represents an integer, and denotes the
number of the line in the source file where the construction occurred.
- Several instances of <c><![CDATA[LINE]]></c> in the same construction may denote
+ Several instances of <c>LINE</c> in the same construction may denote
different lines.</p>
<p>Since operators are not terms in their own right, when operators are
mentioned below, the representation of an operator should be taken to
@@ -66,24 +66,24 @@
function declarations or attributes.</p>
<list type="bulleted">
<item>If D is a module declaration consisting of the forms
- <c><![CDATA[F_1]]></c>, ..., <c><![CDATA[F_k]]></c>, then
- Rep(D) = <c><![CDATA[[Rep(F_1), ..., Rep(F_k)]]]></c>.</item>
- <item>If F is an attribute <c><![CDATA[-module(Mod)]]></c>, then
- Rep(F) = <c><![CDATA[{attribute,LINE,module,Mod}]]></c>.</item>
- <item>If F is an attribute <c><![CDATA[-behavior(Behavior)]]></c>, then
- Rep(F) = <c><![CDATA[{attribute,LINE,behavior,Behavior}]]></c>.</item>
- <item>If F is an attribute <c><![CDATA[-behaviour(Behaviour)]]></c>, then
- Rep(F) = <c><![CDATA[{attribute,LINE,behaviour,Behaviour}]]></c>.</item>
- <item>If F is an attribute <c><![CDATA[-export([Fun_1/A_1, ..., Fun_k/A_k])]]></c>, then
- Rep(F) = <c><![CDATA[{attribute,LINE,export,[{Fun_1,A_1}, ..., {Fun_k,A_k}]}]]></c>.</item>
- <item>If F is an attribute <c><![CDATA[-import(Mod,[Fun_1/A_1, ..., Fun_k/A_k])]]></c>, then
- Rep(F) = <c><![CDATA[{attribute,LINE,import,{Mod,[{Fun_1,A_1}, ..., {Fun_k,A_k}]}}]]></c>.</item>
- <item>If F is an attribute <c><![CDATA[-export_type([Type_1/A_1, ..., Type_k/A_k])]]></c>, then
- Rep(F) = <c><![CDATA[{attribute,LINE,export_type,[{Type_1,A_1}, ..., {Type_k,A_k}]}]]></c>.</item>
- <item>If F is an attribute <c><![CDATA[-compile(Options)]]></c>, then
- Rep(F) = <c><![CDATA[{attribute,LINE,compile,Options}]]></c>.</item>
- <item>If F is an attribute <c><![CDATA[-file(File,Line)]]></c>, then
- Rep(F) = <c><![CDATA[{attribute,LINE,file,{File,Line}}]]></c>.</item>
+ <c>F_1</c>, ..., <c>F_k</c>, then
+ Rep(D) = <c>[Rep(F_1), ..., Rep(F_k)]</c>.</item>
+ <item>If F is an attribute <c>-module(Mod)</c>, then
+ Rep(F) = <c>{attribute,LINE,module,Mod}</c>.</item>
+ <item>If F is an attribute <c>-behavior(Behavior)</c>, then
+ Rep(F) = <c>{attribute,LINE,behavior,Behavior}</c>.</item>
+ <item>If F is an attribute <c>-behaviour(Behaviour)</c>, then
+ Rep(F) = <c>{attribute,LINE,behaviour,Behaviour}</c>.</item>
+ <item>If F is an attribute <c>-export([Fun_1/A_1, ..., Fun_k/A_k])</c>, then
+ Rep(F) = <c>{attribute,LINE,export,[{Fun_1,A_1}, ..., {Fun_k,A_k}]}</c>.</item>
+ <item>If F is an attribute <c>-import(Mod,[Fun_1/A_1, ..., Fun_k/A_k])</c>, then
+ Rep(F) = <c>{attribute,LINE,import,{Mod,[{Fun_1,A_1}, ..., {Fun_k,A_k}]}}</c>.</item>
+ <item>If F is an attribute <c>-export_type([Type_1/A_1, ..., Type_k/A_k])</c>, then
+ Rep(F) = <c>{attribute,LINE,export_type,[{Type_1,A_1}, ..., {Type_k,A_k}]}</c>.</item>
+ <item>If F is an attribute <c>-compile(Options)</c>, then
+ Rep(F) = <c>{attribute,LINE,compile,Options}</c>.</item>
+ <item>If F is an attribute <c>-file(File,Line)</c>, then
+ Rep(F) = <c>{attribute,LINE,file,{File,Line}}</c>.</item>
<item>If F is a record declaration
<c>-record(Name,{V_1, ..., V_k})</c>, then Rep(F) =
<c>{attribute,LINE,record,{Name,[Rep(V_1), ..., Rep(V_k)]}}</c>.
@@ -109,8 +109,8 @@
<c>Arity</c>, then Rep(F) =
<c>{attribute,Line,spec,{{Mod,Name,Arity},[Rep(Ft_1), ..., Rep(Ft_k)]}}</c>.
</item>
- <item>If F is a wild attribute <c><![CDATA[-A(T)]]></c>, then
- Rep(F) = <c><![CDATA[{attribute,LINE,A,T}]]></c>.
+ <item>If F is a wild attribute <c>-A(T)</c>, then
+ Rep(F) = <c>{attribute,LINE,A,T}</c>.
<br></br></item>
<item>If F is a function declaration
<c>Name Fc_1 ; ... ; Name Fc_k</c>,
@@ -126,11 +126,11 @@
explicit default initializer expression, as well as an
optional type.</p>
<list type="bulleted">
- <item>If V is <c><![CDATA[A]]></c>, then
- Rep(V) = <c><![CDATA[{record_field,LINE,Rep(A)}]]></c>.</item>
- <item>If V is <c><![CDATA[A = E]]></c>,
+ <item>If V is <c>A</c>, then
+ Rep(V) = <c>{record_field,LINE,Rep(A)}</c>.</item>
+ <item>If V is <c>A = E</c>,
where <c>E</c> is an expression, then
- Rep(V) = <c><![CDATA[{record_field,LINE,Rep(A),Rep(E)}]]></c>.</item>
+ Rep(V) = <c>{record_field,LINE,Rep(A),Rep(E)}</c>.</item>
<item>If V is <c>A :: T</c>, where <c>T</c> is a
type and it does not contain
<c>undefined</c> syntactically, then Rep(V) =
@@ -163,14 +163,14 @@
same way in patterns, expressions and guards:</p>
<list type="bulleted">
<item>If L is an integer or character literal, then
- Rep(L) = <c><![CDATA[{integer,LINE,L}]]></c>.</item>
+ Rep(L) = <c>{integer,LINE,L}</c>.</item>
<item>If L is a float literal, then
- Rep(L) = <c><![CDATA[{float,LINE,L}]]></c>.</item>
+ Rep(L) = <c>{float,LINE,L}</c>.</item>
<item>If L is a string literal consisting of the characters
- <c><![CDATA[C_1]]></c>, ..., <c><![CDATA[C_k]]></c>, then
- Rep(L) = <c><![CDATA[{string,LINE,[C_1, ..., C_k]}]]></c>.</item>
+ <c>C_1</c>, ..., <c>C_k</c>, then
+ Rep(L) = <c>{string,LINE,[C_1, ..., C_k]}</c>.</item>
<item>If L is an atom literal, then
- Rep(L) = <c><![CDATA[{atom,LINE,L}]]></c>.</item>
+ Rep(L) = <c>{atom,LINE,L}</c>.</item>
</list>
<p>Note that negative integer and float literals do not occur as such; they are
parsed as an application of the unary negation operator.</p>
@@ -178,46 +178,46 @@
<section>
<title>Patterns</title>
- <p>If <c><![CDATA[Ps]]></c> is a sequence of patterns <c><![CDATA[P_1, ..., P_k]]></c>, then
- Rep(Ps) = <c><![CDATA[[Rep(P_1), ..., Rep(P_k)]]]></c>. Such sequences occur as the
+ <p>If <c>Ps</c> is a sequence of patterns <c>P_1, ..., P_k</c>, then
+ Rep(Ps) = <c>[Rep(P_1), ..., Rep(P_k)]</c>. Such sequences occur as the
list of arguments to a function or fun.</p>
<p>Individual patterns are represented as follows:</p>
<list type="bulleted">
<item>If P is an atomic literal L, then Rep(P) = Rep(L).</item>
- <item>If P is a compound pattern <c><![CDATA[P_1 = P_2]]></c>, then
- Rep(P) = <c><![CDATA[{match,LINE,Rep(P_1),Rep(P_2)}]]></c>.</item>
- <item>If P is a variable pattern <c><![CDATA[V]]></c>, then
- Rep(P) = <c><![CDATA[{var,LINE,A}]]></c>,
+ <item>If P is a compound pattern <c>P_1 = P_2</c>, then
+ Rep(P) = <c>{match,LINE,Rep(P_1),Rep(P_2)}</c>.</item>
+ <item>If P is a variable pattern <c>V</c>, then
+ Rep(P) = <c>{var,LINE,A}</c>,
where A is an atom with a printname consisting of the same characters as
- <c><![CDATA[V]]></c>.</item>
- <item>If P is a universal pattern <c><![CDATA[_]]></c>, then
- Rep(P) = <c><![CDATA[{var,LINE,'_'}]]></c>.</item>
- <item>If P is a tuple pattern <c><![CDATA[{P_1, ..., P_k}]]></c>, then
- Rep(P) = <c><![CDATA[{tuple,LINE,[Rep(P_1), ..., Rep(P_k)]}]]></c>.</item>
- <item>If P is a nil pattern <c><![CDATA[[]]]></c>, then
- Rep(P) = <c><![CDATA[{nil,LINE}]]></c>.</item>
- <item>If P is a cons pattern <c><![CDATA[[P_h | P_t]]]></c>, then
- Rep(P) = <c><![CDATA[{cons,LINE,Rep(P_h),Rep(P_t)}]]></c>.</item>
- <item>If E is a binary pattern <c><![CDATA[<<P_1:Size_1/TSL_1, ..., P_k:Size_k/TSL_k>>]]></c>, then
- Rep(E) = <c><![CDATA[{bin,LINE,[{bin_element,LINE,Rep(P_1),Rep(Size_1),Rep(TSL_1)}, ..., {bin_element,LINE,Rep(P_k),Rep(Size_k),Rep(TSL_k)}]}]]></c>.
+ <c>V</c>.</item>
+ <item>If P is a universal pattern <c>_</c>, then
+ Rep(P) = <c>{var,LINE,'_'}</c>.</item>
+ <item>If P is a tuple pattern <c>{P_1, ..., P_k}</c>, then
+ Rep(P) = <c>{tuple,LINE,[Rep(P_1), ..., Rep(P_k)]}</c>.</item>
+ <item>If P is a nil pattern <c>[]</c>, then
+ Rep(P) = <c>{nil,LINE}</c>.</item>
+ <item>If P is a cons pattern <c>[P_h | P_t]</c>, then
+ Rep(P) = <c>{cons,LINE,Rep(P_h),Rep(P_t)}</c>.</item>
+ <item>If E is a binary pattern <c>&lt;&lt;P_1:Size_1/TSL_1, ..., P_k:Size_k/TSL_k>></c>, then
+ Rep(E) = <c>{bin,LINE,[{bin_element,LINE,Rep(P_1),Rep(Size_1),Rep(TSL_1)}, ..., {bin_element,LINE,Rep(P_k),Rep(Size_k),Rep(TSL_k)}]}</c>.
For Rep(TSL), see below.
- An omitted <c><![CDATA[Size]]></c> is represented by <c><![CDATA[default]]></c>. An omitted <c><![CDATA[TSL]]></c>
- (type specifier list) is represented by <c><![CDATA[default]]></c>.</item>
- <item>If P is <c><![CDATA[P_1 Op P_2]]></c>, where <c><![CDATA[Op]]></c> is a binary operator (this
- is either an occurrence of <c><![CDATA[++]]></c> applied to a literal string or character
+ An omitted <c>Size</c> is represented by <c>default</c>. An omitted <c>TSL</c>
+ (type specifier list) is represented by <c>default</c>.</item>
+ <item>If P is <c>P_1 Op P_2</c>, where <c>Op</c> is a binary operator (this
+ is either an occurrence of <c>++</c> applied to a literal string or character
list, or an occurrence of an expression that can be evaluated to a number
at compile time),
- then Rep(P) = <c><![CDATA[{op,LINE,Op,Rep(P_1),Rep(P_2)}]]></c>.</item>
- <item>If P is <c><![CDATA[Op P_0]]></c>, where <c><![CDATA[Op]]></c> is a unary operator (this is an
+ then Rep(P) = <c>{op,LINE,Op,Rep(P_1),Rep(P_2)}</c>.</item>
+ <item>If P is <c>Op P_0</c>, where <c>Op</c> is a unary operator (this is an
occurrence of an expression that can be evaluated to a number at compile
- time), then Rep(P) = <c><![CDATA[{op,LINE,Op,Rep(P_0)}]]></c>.</item>
- <item>If P is a record pattern <c><![CDATA[#Name{Field_1=P_1, ..., Field_k=P_k}]]></c>,
+ time), then Rep(P) = <c>{op,LINE,Op,Rep(P_0)}</c>.</item>
+ <item>If P is a record pattern <c>#Name{Field_1=P_1, ..., Field_k=P_k}</c>,
then Rep(P) =
- <c><![CDATA[{record,LINE,Name,[{record_field,LINE,Rep(Field_1),Rep(P_1)}, ..., {record_field,LINE,Rep(Field_k),Rep(P_k)}]}]]></c>.</item>
- <item>If P is <c><![CDATA[#Name.Field]]></c>, then
- Rep(P) = <c><![CDATA[{record_index,LINE,Name,Rep(Field)}]]></c>.</item>
- <item>If P is <c><![CDATA[( P_0 )]]></c>, then
- Rep(P) = <c><![CDATA[Rep(P_0)]]></c>,
+ <c>{record,LINE,Name,[{record_field,LINE,Rep(Field_1),Rep(P_1)}, ..., {record_field,LINE,Rep(Field_k),Rep(P_k)}]}</c>.</item>
+ <item>If P is <c>#Name.Field</c>, then
+ Rep(P) = <c>{record_index,LINE,Name,Rep(Field)}</c>.</item>
+ <item>If P is <c>( P_0 )</c>, then
+ Rep(P) = <c>Rep(P_0)</c>,
that is, patterns cannot be distinguished from their bodies.</item>
</list>
<p>Note that every pattern has the same source form as some expression, and is
@@ -226,159 +226,153 @@
<section>
<title>Expressions</title>
- <p>A body B is a sequence of expressions <c><![CDATA[E_1, ..., E_k]]></c>, and
- Rep(B) = <c><![CDATA[[Rep(E_1), ..., Rep(E_k)]]]></c>.</p>
+ <p>A body B is a sequence of expressions <c>E_1, ..., E_k</c>, and
+ Rep(B) = <c>[Rep(E_1), ..., Rep(E_k)]</c>.</p>
<p>An expression E is one of the following alternatives:</p>
<list type="bulleted">
- <item>If P is an atomic literal <c><![CDATA[L]]></c>, then
- Rep(P) = Rep(L).</item>
- <item>If E is <c><![CDATA[P = E_0]]></c>, then
- Rep(E) = <c><![CDATA[{match,LINE,Rep(P),Rep(E_0)}]]></c>.</item>
- <item>If E is a variable <c><![CDATA[V]]></c>, then
- Rep(E) = <c><![CDATA[{var,LINE,A}]]></c>,
- where <c><![CDATA[A]]></c> is an atom with a printname consisting of the same
- characters as <c><![CDATA[V]]></c>.</item>
- <item>If E is a tuple skeleton <c><![CDATA[{E_1, ..., E_k}]]></c>, then
- Rep(E) = <c><![CDATA[{tuple,LINE,[Rep(E_1), ..., Rep(E_k)]}]]></c>.</item>
- <item>If E is <c><![CDATA[[]]]></c>, then
- Rep(E) = <c><![CDATA[{nil,LINE}]]></c>.</item>
- <item>If E is a cons skeleton <c><![CDATA[[E_h | E_t]]]></c>, then
- Rep(E) = <c><![CDATA[{cons,LINE,Rep(E_h),Rep(E_t)}]]></c>.</item>
- <item>If E is a binary constructor <c><![CDATA[<<V_1:Size_1/TSL_1, ..., V_k:Size_k/TSL_k>>]]></c>, then
- Rep(E) = <c><![CDATA[{bin,LINE,[{bin_element,LINE,Rep(V_1),Rep(Size_1),Rep(TSL_1)}, ..., {bin_element,LINE,Rep(V_k),Rep(Size_k),Rep(TSL_k)}]}]]></c>.
+ <item>If P is an atomic literal <c>L</c>, then Rep(P) = Rep(L).</item>
+ <item>If E is <c>P = E_0</c>, then
+ Rep(E) = <c>{match,LINE,Rep(P),Rep(E_0)}</c>.</item>
+ <item>If E is a variable <c>V</c>, then Rep(E) = <c>{var,LINE,A}</c>,
+ where <c>A</c> is an atom with a printname consisting of the same
+ characters as <c>V</c>.</item>
+ <item>If E is a tuple skeleton <c>{E_1, ..., E_k}</c>, then
+ Rep(E) = <c>{tuple,LINE,[Rep(E_1), ..., Rep(E_k)]}</c>.</item>
+ <item>If E is <c>[]</c>, then
+ Rep(E) = <c>{nil,LINE}</c>.</item>
+ <item>If E is a cons skeleton <c>[E_h | E_t]</c>, then
+ Rep(E) = <c>{cons,LINE,Rep(E_h),Rep(E_t)}</c>.</item>
+ <item>If E is a binary constructor <c>&lt;&lt;V_1:Size_1/TSL_1, ..., V_k:Size_k/TSL_k>></c>, then Rep(E) =
+ <c>{bin,LINE,[{bin_element,LINE,Rep(V_1),Rep(Size_1),Rep(TSL_1)}, ..., {bin_element,LINE,Rep(V_k),Rep(Size_k),Rep(TSL_k)}]}</c>.
For Rep(TSL), see below.
- An omitted <c><![CDATA[Size]]></c> is represented by <c><![CDATA[default]]></c>. An omitted <c><![CDATA[TSL]]></c>
- (type specifier list) is represented by <c><![CDATA[default]]></c>.</item>
- <item>If E is <c><![CDATA[E_1 Op E_2]]></c>, where <c><![CDATA[Op]]></c> is a binary operator,
- then Rep(E) = <c><![CDATA[{op,LINE,Op,Rep(E_1),Rep(E_2)}]]></c>.</item>
- <item>If E is <c><![CDATA[Op E_0]]></c>, where <c><![CDATA[Op]]></c> is a unary operator, then
- Rep(E) = <c><![CDATA[{op,LINE,Op,Rep(E_0)}]]></c>.</item>
- <item>If E is <c><![CDATA[#Name{Field_1=E_1, ..., Field_k=E_k}]]></c>, then
- Rep(E) =
- <c><![CDATA[{record,LINE,Name,[{record_field,LINE,Rep(Field_1),Rep(E_1)}, ..., {record_field,LINE,Rep(Field_k),Rep(E_k)}]}]]></c>.</item>
- <item>If E is <c><![CDATA[E_0#Name{Field_1=E_1, ..., Field_k=E_k}]]></c>, then
- Rep(E) =
- <c><![CDATA[{record,LINE,Rep(E_0),Name,[{record_field,LINE,Rep(Field_1),Rep(E_1)}, ..., {record_field,LINE,Rep(Field_k),Rep(E_k)}]}]]></c>.</item>
- <item>If E is <c><![CDATA[#Name.Field]]></c>, then
- Rep(E) = <c><![CDATA[{record_index,LINE,Name,Rep(Field)}]]></c>.</item>
- <item>If E is <c><![CDATA[E_0#Name.Field]]></c>, then
- Rep(E) = <c><![CDATA[{record_field,LINE,Rep(E_0),Name,Rep(Field)}]]></c>.</item>
- <item>If E is <c><![CDATA[#{W_1, ..., W_k}]]></c> where each
- <c><![CDATA[W_i]]></c> is a map assoc or exact field, then Rep(E) =
- <c><![CDATA[{map,LINE,[Rep(W_1), ..., Rep(W_k)]}]]></c>. For Rep(W), see
- below.</item>
- <item>If E is <c><![CDATA[E_0#{W_1, ..., W_k}]]></c> where
- <c><![CDATA[W_i]]></c> is a map assoc or exact field, then Rep(E) =
- <c><![CDATA[{map,LINE,Rep(E_0),[Rep(W_1), ..., Rep(W_k)]}]]></c>. For
- Rep(W), see below.</item>
- <item>If E is <c><![CDATA[catch E_0]]></c>, then
- Rep(E) = <c><![CDATA[{'catch',LINE,Rep(E_0)}]]></c>.</item>
- <item>If E is <c><![CDATA[E_0(E_1, ..., E_k)]]></c>, then
- Rep(E) = <c><![CDATA[{call,LINE,Rep(E_0),[Rep(E_1), ..., Rep(E_k)]}]]></c>.</item>
- <item>If E is <c><![CDATA[E_m:E_0(E_1, ..., E_k)]]></c>, then
+ An omitted <c>Size</c> is represented by <c>default</c>. An omitted <c>TSL</c>
+ (type specifier list) is represented by <c>default</c>.</item>
+ <item>If E is <c>E_1 Op E_2</c>, where <c>Op</c> is a binary operator,
+ then Rep(E) = <c>{op,LINE,Op,Rep(E_1),Rep(E_2)}</c>.</item>
+ <item>If E is <c>Op E_0</c>, where <c>Op</c> is a unary operator, then
+ Rep(E) = <c>{op,LINE,Op,Rep(E_0)}</c>.</item>
+ <item>If E is <c>#Name{Field_1=E_1, ..., Field_k=E_k}</c>,
+ then Rep(E) =
+ <c>{record,LINE,Name,[{record_field,LINE,Rep(Field_1),Rep(E_1)}, ..., {record_field,LINE,Rep(Field_k),Rep(E_k)}]}</c>.</item>
+ <item>If E is <c>E_0#Name{Field_1=E_1, ..., Field_k=E_k}</c>, then
Rep(E) =
- <c><![CDATA[{call,LINE,{remote,LINE,Rep(E_m),Rep(E_0)},[Rep(E_1), ..., Rep(E_k)]}]]></c>.</item>
- <item>If E is a list comprehension <c><![CDATA[[E_0 || W_1, ..., W_k]]]></c>,
- where each <c><![CDATA[W_i]]></c> is a generator or a filter, then
- Rep(E) = <c><![CDATA[{lc,LINE,Rep(E_0),[Rep(W_1), ..., Rep(W_k)]}]]></c>. For Rep(W), see
+ <c>{record,LINE,Rep(E_0),Name,[{record_field,LINE,Rep(Field_1),Rep(E_1)}, ..., {record_field,LINE,Rep(Field_k),Rep(E_k)}]}</c>.</item>
+ <item>If E is <c>#Name.Field</c>, then
+ Rep(E) = <c>{record_index,LINE,Name,Rep(Field)}</c>.</item>
+ <item>If E is <c>E_0#Name.Field</c>, then
+ Rep(E) = <c>{record_field,LINE,Rep(E_0),Name,Rep(Field)}</c>.</item>
+ <item>If E is <c>#{W_1, ..., W_k}</c> where each
+ <c>W_i</c> is a map assoc or exact field, then Rep(E) =
+ <c>{map,LINE,[Rep(W_1), ..., Rep(W_k)]}</c>. For Rep(W), see
below.</item>
- <item>If E is a binary comprehension <c><![CDATA[<<E_0 || W_1, ..., W_k>>]]></c>,
- where each <c><![CDATA[W_i]]></c> is a generator or a filter, then
- Rep(E) = <c><![CDATA[{bc,LINE,Rep(E_0),[Rep(W_1), ..., Rep(W_k)]}]]></c>. For Rep(W), see
+ <item>If E is <c>E_0#{W_1, ..., W_k}</c> where
+ <c>W_i</c> is a map assoc or exact field, then Rep(E) =
+ <c>{map,LINE,Rep(E_0),[Rep(W_1), ..., Rep(W_k)]}</c>.
+ For Rep(W), see below.</item>
+ <item>If E is <c>catch E_0</c>, then
+ Rep(E) = <c>{'catch',LINE,Rep(E_0)}</c>.</item>
+ <item>If E is <c>E_0(E_1, ..., E_k)</c>, then
+ Rep(E) = <c>{call,LINE,Rep(E_0),[Rep(E_1), ..., Rep(E_k)]}</c>.</item>
+ <item>If E is <c>E_m:E_0(E_1, ..., E_k)</c>, then Rep(E) =
+ <c>{call,LINE,{remote,LINE,Rep(E_m),Rep(E_0)},[Rep(E_1), ..., Rep(E_k)]}</c>.
+ </item>
+ <item>If E is a list comprehension <c>[E_0 || W_1, ..., W_k]</c>,
+ where each <c>W_i</c> is a generator or a filter, then Rep(E) =
+ <c>{lc,LINE,Rep(E_0),[Rep(W_1), ..., Rep(W_k)]}</c>. For Rep(W), see
below.</item>
- <item>If E is <c><![CDATA[begin B end]]></c>, where <c><![CDATA[B]]></c> is a body, then
- Rep(E) = <c><![CDATA[{block,LINE,Rep(B)}]]></c>.</item>
- <item>If E is <c><![CDATA[if Ic_1 ; ... ; Ic_k end]]></c>,
- where each <c><![CDATA[Ic_i]]></c> is an if clause then
- Rep(E) =
- <c><![CDATA[{'if',LINE,[Rep(Ic_1), ..., Rep(Ic_k)]}]]></c>.</item>
- <item>If E is <c><![CDATA[case E_0 of Cc_1 ; ... ; Cc_k end]]></c>,
- where <c><![CDATA[E_0]]></c> is an expression and each <c><![CDATA[Cc_i]]></c> is a
- case clause then
- Rep(E) =
- <c><![CDATA[{'case',LINE,Rep(E_0),[Rep(Cc_1), ..., Rep(Cc_k)]}]]></c>.</item>
- <item>If E is <c><![CDATA[try B catch Tc_1 ; ... ; Tc_k end]]></c>,
- where <c><![CDATA[B]]></c> is a body and each <c><![CDATA[Tc_i]]></c> is a catch clause then
+ <item>If E is a binary comprehension
+ <c>&lt;&lt;E_0 || W_1, ..., W_k>></c>,
+ where each <c>W_i</c> is a generator or a filter, then
+ Rep(E) = <c>{bc,LINE,Rep(E_0),[Rep(W_1), ..., Rep(W_k)]}</c>.
+ For Rep(W), see below.</item>
+ <item>If E is <c>begin B end</c>, where <c>B</c> is a body, then
+ Rep(E) = <c>{block,LINE,Rep(B)}</c>.</item>
+ <item>If E is <c>if Ic_1 ; ... ; Ic_k end</c>,
+ where each <c>Ic_i</c> is an if clause then Rep(E) =
+ <c>{'if',LINE,[Rep(Ic_1), ..., Rep(Ic_k)]}</c>.</item>
+ <item>If E is <c>case E_0 of Cc_1 ; ... ; Cc_k end</c>,
+ where <c>E_0</c> is an expression and each <c>Cc_i</c> is a
+ case clause then Rep(E) =
+ <c>{'case',LINE,Rep(E_0),[Rep(Cc_1), ..., Rep(Cc_k)]}</c>.</item>
+ <item>If E is <c>try B catch Tc_1 ; ... ; Tc_k end</c>,
+ where <c>B</c> is a body and each <c>Tc_i</c> is a catch clause then
Rep(E) =
- <c><![CDATA[{'try',LINE,Rep(B),[],[Rep(Tc_1), ..., Rep(Tc_k)],[]}]]></c>.</item>
- <item>If E is <c><![CDATA[try B of Cc_1 ; ... ; Cc_k catch Tc_1 ; ... ; Tc_n end]]></c>,
- where <c><![CDATA[B]]></c> is a body,
- each <c><![CDATA[Cc_i]]></c> is a case clause and
- each <c><![CDATA[Tc_j]]></c> is a catch clause then
+ <c>{'try',LINE,Rep(B),[],[Rep(Tc_1), ..., Rep(Tc_k)],[]}</c>.</item>
+ <item>If E is <c>try B of Cc_1 ; ... ; Cc_k catch Tc_1 ; ... ; Tc_n end</c>,
+ where <c>B</c> is a body,
+ each <c>Cc_i</c> is a case clause and
+ each <c>Tc_j</c> is a catch clause then Rep(E) =
+ <c>{'try',LINE,Rep(B),[Rep(Cc_1), ..., Rep(Cc_k)],[Rep(Tc_1), ..., Rep(Tc_n)],[]}</c>.</item>
+ <item>If E is <c>try B after A end</c>,
+ where <c>B</c> and <c>A</c> are bodies then Rep(E) =
+ <c>{'try',LINE,Rep(B),[],[],Rep(A)}</c>.</item>
+ <item>If E is <c>try B of Cc_1 ; ... ; Cc_k after A end</c>,
+ where <c>B</c> and <c>A</c> are a bodies and
+ each <c>Cc_i</c> is a case clause then Rep(E) =
+ <c>{'try',LINE,Rep(B),[Rep(Cc_1), ..., Rep(Cc_k)],[],Rep(A)}</c>.</item>
+ <item>If E is <c>try B catch Tc_1 ; ... ; Tc_k after A end</c>,
+ where <c>B</c> and <c>A</c> are bodies and
+ each <c>Tc_i</c> is a catch clause then Rep(E) =
+ <c>{'try',LINE,Rep(B),[],[Rep(Tc_1), ..., Rep(Tc_k)],Rep(A)}</c>.</item>
+ <item>If E is <c>try B of Cc_1 ; ... ; Cc_k catch Tc_1 ; ... ; Tc_n after A end</c>,
+ where <c>B</c> and <c>A</c> are a bodies,
+ each <c>Cc_i</c> is a case clause and
+ each <c>Tc_j</c> is a catch clause then
Rep(E) =
- <c><![CDATA[{'try',LINE,Rep(B),[Rep(Cc_1), ..., Rep(Cc_k)],[Rep(Tc_1), ..., Rep(Tc_n)],[]}]]></c>.</item>
- <item>If E is <c><![CDATA[try B after A end]]></c>,
- where <c><![CDATA[B]]></c> and <c><![CDATA[A]]></c> are bodies then
- Rep(E) =
- <c><![CDATA[{'try',LINE,Rep(B),[],[],Rep(A)}]]></c>.</item>
- <item>If E is <c><![CDATA[try B of Cc_1 ; ... ; Cc_k after A end]]></c>,
- where <c><![CDATA[B]]></c> and <c><![CDATA[A]]></c> are a bodies and
- each <c><![CDATA[Cc_i]]></c> is a case clause then
- Rep(E) =
- <c><![CDATA[{'try',LINE,Rep(B),[Rep(Cc_1), ..., Rep(Cc_k)],[],Rep(A)}]]></c>.</item>
- <item>If E is <c><![CDATA[try B catch Tc_1 ; ... ; Tc_k after A end]]></c>,
- where <c><![CDATA[B]]></c> and <c><![CDATA[A]]></c> are bodies and
- each <c><![CDATA[Tc_i]]></c> is a catch clause then
- Rep(E) =
- <c><![CDATA[{'try',LINE,Rep(B),[],[Rep(Tc_1), ..., Rep(Tc_k)],Rep(A)}]]></c>.</item>
- <item>If E is <c><![CDATA[try B of Cc_1 ; ... ; Cc_k catch Tc_1 ; ... ; Tc_n after A end]]></c>,
- where <c><![CDATA[B]]></c> and <c><![CDATA[A]]></c> are a bodies,
- each <c><![CDATA[Cc_i]]></c> is a case clause and
- each <c><![CDATA[Tc_j]]></c> is a catch clause then
- Rep(E) =
- <c><![CDATA[{'try',LINE,Rep(B),[Rep(Cc_1), ..., Rep(Cc_k)],[Rep(Tc_1), ..., Rep(Tc_n)],Rep(A)}]]></c>.</item>
- <item>If E is <c><![CDATA[receive Cc_1 ; ... ; Cc_k end]]></c>,
- where each <c><![CDATA[Cc_i]]></c> is a case clause then
- Rep(E) =
- <c><![CDATA[{'receive',LINE,[Rep(Cc_1), ..., Rep(Cc_k)]}]]></c>.</item>
- <item>If E is <c><![CDATA[receive Cc_1 ; ... ; Cc_k after E_0 -> B_t end]]></c>,
- where each <c><![CDATA[Cc_i]]></c> is a case clause,
- <c><![CDATA[E_0]]></c> is an expression and <c><![CDATA[B_t]]></c> is a body, then
- Rep(E) =
- <c><![CDATA[{'receive',LINE,[Rep(Cc_1), ..., Rep(Cc_k)],Rep(E_0),Rep(B_t)}]]></c>.</item>
- <item>If E is <c><![CDATA[fun Name / Arity]]></c>, then
- Rep(E) = <c><![CDATA[{'fun',LINE,{function,Name,Arity}}]]></c>.</item>
- <item>If E is <c><![CDATA[fun Module:Name/Arity]]></c>, then
- Rep(E) = <c><![CDATA[{'fun',LINE,{function,Rep(Module),Rep(Name),Rep(Arity)}}]]></c>.
- (Before the R15 release: Rep(E) = <c><![CDATA[{'fun',LINE,{function,Module,Name,Arity}}]]></c>.)</item>
- <item>If E is <c><![CDATA[fun Fc_1 ; ... ; Fc_k end]]></c>
- where each <c><![CDATA[Fc_i]]></c> is a function clause then Rep(E) =
- <c><![CDATA[{'fun',LINE,{clauses,[Rep(Fc_1), ..., Rep(Fc_k)]}}]]></c>.</item>
- <item>If E is <c><![CDATA[fun Name Fc_1 ; ... ; Name Fc_k end]]></c>
- where <c><![CDATA[Name]]></c> is a variable and each
- <c><![CDATA[Fc_i]]></c> is a function clause then Rep(E) =
- <c><![CDATA[{named_fun,LINE,Name,[Rep(Fc_1), ..., Rep(Fc_k)]}]]></c>.
+ <c>{'try',LINE,Rep(B),[Rep(Cc_1), ..., Rep(Cc_k)],[Rep(Tc_1), ..., Rep(Tc_n)],Rep(A)}</c>.</item>
+ <item>If E is <c>receive Cc_1 ; ... ; Cc_k end</c>,
+ where each <c>Cc_i</c> is a case clause then Rep(E) =
+ <c>{'receive',LINE,[Rep(Cc_1), ..., Rep(Cc_k)]}</c>.</item>
+ <item>If E is <c>receive Cc_1 ; ... ; Cc_k after E_0 -> B_t end</c>,
+ where each <c>Cc_i</c> is a case clause,
+ <c>E_0</c> is an expression and <c>B_t</c> is a body, then Rep(E) =
+ <c>{'receive',LINE,[Rep(Cc_1), ..., Rep(Cc_k)],Rep(E_0),Rep(B_t)}</c>.</item>
+ <item>If E is <c>fun Name / Arity</c>, then
+ Rep(E) = <c>{'fun',LINE,{function,Name,Arity}}</c>.</item>
+ <item>If E is <c>fun Module:Name/Arity</c>, then Rep(E) =
+ <c>{'fun',LINE,{function,Rep(Module),Rep(Name),Rep(Arity)}}</c>.
+ (Before the R15 release: Rep(E) =
+ <c>{'fun',LINE,{function,Module,Name,Arity}}</c>.)</item>
+ <item>If E is <c>fun Fc_1 ; ... ; Fc_k end</c>
+ where each <c>Fc_i</c> is a function clause then Rep(E) =
+ <c>{'fun',LINE,{clauses,[Rep(Fc_1), ..., Rep(Fc_k)]}}</c>.</item>
+ <item>If E is <c>fun Name Fc_1 ; ... ; Name Fc_k end</c>
+ where <c>Name</c> is a variable and each
+ <c>Fc_i</c> is a function clause then Rep(E) =
+ <c>{named_fun,LINE,Name,[Rep(Fc_1), ..., Rep(Fc_k)]}</c>.
</item>
- <item>If E is <c><![CDATA[( E_0 )]]></c>, then
+ <item>If E is <c>( E_0 )</c>, then
Rep(E) = <c>Rep(E_0)</c>, that is, parenthesized
expressions cannot be distinguished from their bodies.</item>
</list>
<section>
<title>Generators and Filters</title>
- <p>When W is a generator or a filter (in the body of a list or binary comprehension), then:</p>
+ <p>When W is a generator or a filter (in the body of a list or
+ binary comprehension), then:</p>
<list type="bulleted">
- <item>If W is a generator <c><![CDATA[P <- E]]></c>, where <c><![CDATA[P]]></c> is a pattern and <c><![CDATA[E]]></c>
- is an expression, then
- Rep(W) = <c><![CDATA[{generate,LINE,Rep(P),Rep(E)}]]></c>.</item>
- <item>If W is a generator <c><![CDATA[P <= E]]></c>, where <c><![CDATA[P]]></c> is a pattern and <c><![CDATA[E]]></c>
- is an expression, then
- Rep(W) = <c><![CDATA[{b_generate,LINE,Rep(P),Rep(E)}]]></c>.</item>
- <item>If W is a filter <c><![CDATA[E]]></c>, which is an expression, then
- Rep(W) = <c><![CDATA[Rep(E)]]></c>.</item>
+ <item>If W is a generator <c>P &lt;- E</c>, where <c>P</c> is
+ a pattern and <c>E</c> is an expression, then
+ Rep(W) = <c>{generate,LINE,Rep(P),Rep(E)}</c>.</item>
+ <item>If W is a generator <c>P &lt;= E</c>, where <c>P</c> is
+ a pattern and <c>E</c> is an expression, then
+ Rep(W) = <c>{b_generate,LINE,Rep(P),Rep(E)}</c>.</item>
+ <item>If W is a filter <c>E</c>, which is an expression, then
+ Rep(W) = <c>Rep(E)</c>.</item>
</list>
</section>
<section>
<title>Binary Element Type Specifiers</title>
<p>A type specifier list TSL for a binary element is a sequence of type
- specifiers <c><![CDATA[TS_1 - ... - TS_k]]></c>.
- Rep(TSL) = <c><![CDATA[[Rep(TS_1), ..., Rep(TS_k)]]]></c>.</p>
+ specifiers <c>TS_1 - ... - TS_k</c>.
+ Rep(TSL) = <c>[Rep(TS_1), ..., Rep(TS_k)]</c>.</p>
<p>When TS is a type specifier for a binary element, then:</p>
<list type="bulleted">
- <item>If TS is an atom <c><![CDATA[A]]></c>, then Rep(TS) = <c><![CDATA[A]]></c>.</item>
- <item>If TS is a couple <c><![CDATA[A:Value]]></c> where <c><![CDATA[A]]></c> is an atom and <c><![CDATA[Value]]></c>
- is an integer, then Rep(TS) = <c>{A,Value}</c>.</item>
+ <item>If TS is an atom <c>A</c>, then Rep(TS) = <c>A</c>.</item>
+ <item>If TS is a couple <c>A:Value</c> where <c>A</c> is an atom
+ and <c>Value</c> is an integer, then Rep(TS) =
+ <c>{A,Value}</c>.</item>
</list>
</section>
@@ -386,13 +380,13 @@
<title>Map Assoc and Exact Fields</title>
<p>When W is an assoc or exact field (in the body of a map), then:</p>
<list type="bulleted">
- <item>If W is an assoc field <c><![CDATA[K => V]]></c>, where
- <c><![CDATA[K]]></c> and <c><![CDATA[V]]></c> are both expressions,
- then Rep(W) = <c><![CDATA[{map_field_assoc,LINE,Rep(K),Rep(V)}]]></c>.
+ <item>If W is an assoc field <c>K => V</c>, where
+ <c>K</c> and <c>V</c> are both expressions,
+ then Rep(W) = <c>{map_field_assoc,LINE,Rep(K),Rep(V)}</c>.
</item>
- <item>If W is an exact field <c><![CDATA[K := V]]></c>, where
- <c><![CDATA[K]]></c> and <c><![CDATA[V]]></c> are both expressions,
- then Rep(W) = <c><![CDATA[{map_field_exact,LINE,Rep(K),Rep(V)}]]></c>.
+ <item>If W is an exact field <c>K := V</c>, where
+ <c>K</c> and <c>V</c> are both expressions,
+ then Rep(W) = <c>{map_field_exact,LINE,Rep(K),Rep(V)}</c>.
</item>
</list>
</section>
@@ -400,92 +394,95 @@
<section>
<title>Clauses</title>
- <p>There are function clauses, if clauses, case clauses
+ <p>There are function clauses, if clauses, case clauses
and catch clauses.</p>
- <p>A clause <c><![CDATA[C]]></c> is one of the following alternatives:</p>
+ <p>A clause <c>C</c> is one of the following alternatives:</p>
<list type="bulleted">
- <item>If C is a function clause <c><![CDATA[( Ps ) -> B]]></c>
- where <c><![CDATA[Ps]]></c> is a pattern sequence and <c><![CDATA[B]]></c> is a body, then
- Rep(C) = <c><![CDATA[{clause,LINE,Rep(Ps),[],Rep(B)}]]></c>.</item>
- <item>If C is a function clause <c><![CDATA[( Ps ) when Gs -> B]]></c>
- where <c><![CDATA[Ps]]></c> is a pattern sequence,
- <c><![CDATA[Gs]]></c> is a guard sequence and <c><![CDATA[B]]></c> is a body, then
- Rep(C) = <c><![CDATA[{clause,LINE,Rep(Ps),Rep(Gs),Rep(B)}]]></c>.</item>
- <item>If C is an if clause <c><![CDATA[Gs -> B]]></c>
- where <c><![CDATA[Gs]]></c> is a guard sequence and <c><![CDATA[B]]></c> is a body, then
- Rep(C) = <c><![CDATA[{clause,LINE,[],Rep(Gs),Rep(B)}]]></c>.</item>
- <item>If C is a case clause <c><![CDATA[P -> B]]></c>
- where <c><![CDATA[P]]></c> is a pattern and <c><![CDATA[B]]></c> is a body, then
- Rep(C) = <c><![CDATA[{clause,LINE,[Rep(P)],[],Rep(B)}]]></c>.</item>
- <item>If C is a case clause <c><![CDATA[P when Gs -> B]]></c>
- where <c><![CDATA[P]]></c> is a pattern,
- <c><![CDATA[Gs]]></c> is a guard sequence and <c><![CDATA[B]]></c> is a body, then
- Rep(C) = <c><![CDATA[{clause,LINE,[Rep(P)],Rep(Gs),Rep(B)}]]></c>.</item>
- <item>If C is a catch clause <c><![CDATA[P -> B]]></c>
- where <c><![CDATA[P]]></c> is a pattern and <c><![CDATA[B]]></c> is a body, then
- Rep(C) = <c><![CDATA[{clause,LINE,[Rep({throw,P,_})],[],Rep(B)}]]></c>.</item>
- <item>If C is a catch clause <c><![CDATA[X : P -> B]]></c>
- where <c><![CDATA[X]]></c> is an atomic literal or a variable pattern,
- <c><![CDATA[P]]></c> is a pattern and <c><![CDATA[B]]></c> is a body, then
- Rep(C) = <c><![CDATA[{clause,LINE,[Rep({X,P,_})],[],Rep(B)}]]></c>.</item>
- <item>If C is a catch clause <c><![CDATA[P when Gs -> B]]></c>
- where <c><![CDATA[P]]></c> is a pattern, <c><![CDATA[Gs]]></c> is a guard sequence
- and <c><![CDATA[B]]></c> is a body, then
- Rep(C) = <c><![CDATA[{clause,LINE,[Rep({throw,P,_})],Rep(Gs),Rep(B)}]]></c>.</item>
- <item>If C is a catch clause <c><![CDATA[X : P when Gs -> B]]></c>
- where <c><![CDATA[X]]></c> is an atomic literal or a variable pattern,
- <c><![CDATA[P]]></c> is a pattern, <c><![CDATA[Gs]]></c> is a guard sequence
- and <c><![CDATA[B]]></c> is a body, then
- Rep(C) = <c><![CDATA[{clause,LINE,[Rep({X,P,_})],Rep(Gs),Rep(B)}]]></c>.</item>
+ <item>If C is a function clause <c>( Ps ) -> B</c>
+ where <c>Ps</c> is a pattern sequence and <c>B</c> is a body, then
+ Rep(C) = <c>{clause,LINE,Rep(Ps),[],Rep(B)}</c>.</item>
+ <item>If C is a function clause <c>( Ps ) when Gs -> B</c>
+ where <c>Ps</c> is a pattern sequence,
+ <c>Gs</c> is a guard sequence and <c>B</c> is a body, then
+ Rep(C) = <c>{clause,LINE,Rep(Ps),Rep(Gs),Rep(B)}</c>.</item>
+ <item>If C is an if clause <c>Gs -> B</c>
+ where <c>Gs</c> is a guard sequence and <c>B</c> is a body, then
+ Rep(C) = <c>{clause,LINE,[],Rep(Gs),Rep(B)}</c>.</item>
+ <item>If C is a case clause <c>P -> B</c>
+ where <c>P</c> is a pattern and <c>B</c> is a body, then
+ Rep(C) = <c>{clause,LINE,[Rep(P)],[],Rep(B)}</c>.</item>
+ <item>If C is a case clause <c>P when Gs -> B</c>
+ where <c>P</c> is a pattern,
+ <c>Gs</c> is a guard sequence and <c>B</c> is a body, then
+ Rep(C) = <c>{clause,LINE,[Rep(P)],Rep(Gs),Rep(B)}</c>.</item>
+ <item>If C is a catch clause <c>P -> B</c>
+ where <c>P</c> is a pattern and <c>B</c> is a body, then
+ Rep(C) = <c>{clause,LINE,[Rep({throw,P,_})],[],Rep(B)}</c>.</item>
+ <item>If C is a catch clause <c>X : P -> B</c>
+ where <c>X</c> is an atomic literal or a variable pattern,
+ <c>P</c> is a pattern and <c>B</c> is a body, then
+ Rep(C) = <c>{clause,LINE,[Rep({X,P,_})],[],Rep(B)}</c>.</item>
+ <item>If C is a catch clause <c>P when Gs -> B</c>
+ where <c>P</c> is a pattern, <c>Gs</c> is a guard sequence
+ and <c>B</c> is a body, then
+ Rep(C) = <c>{clause,LINE,[Rep({throw,P,_})],Rep(Gs),Rep(B)}</c>.</item>
+ <item>If C is a catch clause <c>X : P when Gs -> B</c>
+ where <c>X</c> is an atomic literal or a variable pattern,
+ <c>P</c> is a pattern, <c>Gs</c> is a guard sequence
+ and <c>B</c> is a body, then
+ Rep(C) = <c>{clause,LINE,[Rep({X,P,_})],Rep(Gs),Rep(B)}</c>.</item>
</list>
</section>
<section>
<title>Guards</title>
- <p>A guard sequence Gs is a sequence of guards <c><![CDATA[G_1; ...; G_k]]></c>, and
- Rep(Gs) = <c><![CDATA[[Rep(G_1), ..., Rep(G_k)]]]></c>. If the guard sequence is
- empty, Rep(Gs) = <c><![CDATA[[]]]></c>.</p>
- <p>A guard G is a nonempty sequence of guard tests <c><![CDATA[Gt_1, ..., Gt_k]]></c>, and
- Rep(G) = <c><![CDATA[[Rep(Gt_1), ..., Rep(Gt_k)]]]></c>.</p>
- <p>A guard test <c><![CDATA[Gt]]></c> is one of the following alternatives:</p>
+ <p>A guard sequence Gs is a sequence of guards <c>G_1; ...; G_k</c>, and
+ Rep(Gs) = <c>[Rep(G_1), ..., Rep(G_k)]</c>. If the guard sequence is
+ empty, Rep(Gs) = <c>[]</c>.</p>
+ <p>A guard G is a nonempty sequence of guard tests
+ <c>Gt_1, ..., Gt_k</c>, and Rep(G) =
+ <c>[Rep(Gt_1), ..., Rep(Gt_k)]</c>.</p>
+ <p>A guard test <c>Gt</c> is one of the following alternatives:</p>
<list type="bulleted">
<item>If Gt is an atomic literal L, then Rep(Gt) = Rep(L).</item>
- <item>If Gt is a variable pattern <c><![CDATA[V]]></c>, then
- Rep(Gt) = <c><![CDATA[{var,LINE,A}]]></c>,
- where A is an atom with a printname consisting of the same characters as
- <c><![CDATA[V]]></c>.</item>
- <item>If Gt is a tuple skeleton <c><![CDATA[{Gt_1, ..., Gt_k}]]></c>, then
- Rep(Gt) = <c><![CDATA[{tuple,LINE,[Rep(Gt_1), ..., Rep(Gt_k)]}]]></c>.</item>
- <item>If Gt is <c><![CDATA[[]]]></c>, then
- Rep(Gt) = <c><![CDATA[{nil,LINE}]]></c>.</item>
- <item>If Gt is a cons skeleton <c><![CDATA[[Gt_h | Gt_t]]]></c>, then
- Rep(Gt) = <c><![CDATA[{cons,LINE,Rep(Gt_h),Rep(Gt_t)}]]></c>.</item>
- <item>If Gt is a binary constructor <c><![CDATA[<<Gt_1:Size_1/TSL_1, ..., Gt_k:Size_k/TSL_k>>]]></c>, then
- Rep(Gt) = <c><![CDATA[{bin,LINE,[{bin_element,LINE,Rep(Gt_1),Rep(Size_1),Rep(TSL_1)}, ..., {bin_element,LINE,Rep(Gt_k),Rep(Size_k),Rep(TSL_k)}]}]]></c>.
+ <item>If Gt is a variable pattern <c>V</c>, then
+ Rep(Gt) = <c>{var,LINE,A}</c>, where A is an atom with
+ a printname consisting of the same characters as <c>V</c>.</item>
+ <item>If Gt is a tuple skeleton <c>{Gt_1, ..., Gt_k}</c>, then
+ Rep(Gt) = <c>{tuple,LINE,[Rep(Gt_1), ..., Rep(Gt_k)]}</c>.</item>
+ <item>If Gt is <c>[]</c>, then Rep(Gt) = <c>{nil,LINE}</c>.</item>
+ <item>If Gt is a cons skeleton <c>[Gt_h | Gt_t]</c>, then
+ Rep(Gt) = <c>{cons,LINE,Rep(Gt_h),Rep(Gt_t)}</c>.</item>
+ <item>If Gt is a binary constructor
+ <c>&lt;&lt;Gt_1:Size_1/TSL_1, ..., Gt_k:Size_k/TSL_k>></c>, then
+ Rep(Gt) = <c>{bin,LINE,[{bin_element,LINE,Rep(Gt_1),Rep(Size_1),Rep(TSL_1)}, ..., {bin_element,LINE,Rep(Gt_k),Rep(Size_k),Rep(TSL_k)}]}</c>.
For Rep(TSL), see above.
- An omitted <c><![CDATA[Size]]></c> is represented by <c><![CDATA[default]]></c>. An omitted <c><![CDATA[TSL]]></c>
- (type specifier list) is represented by <c><![CDATA[default]]></c>.</item>
- <item>If Gt is <c><![CDATA[Gt_1 Op Gt_2]]></c>, where <c><![CDATA[Op]]></c>
- is a binary operator, then Rep(Gt) = <c><![CDATA[{op,LINE,Op,Rep(Gt_1),Rep(Gt_2)}]]></c>.</item>
- <item>If Gt is <c><![CDATA[Op Gt_0]]></c>, where <c><![CDATA[Op]]></c> is a unary operator, then
- Rep(Gt) = <c><![CDATA[{op,LINE,Op,Rep(Gt_0)}]]></c>.</item>
- <item>If Gt is <c><![CDATA[#Name{Field_1=Gt_1, ..., Field_k=Gt_k}]]></c>, then
+ An omitted <c>Size</c> is represented by <c>default</c>.
+ An omitted <c>TSL</c> (type specifier list) is represented
+ by <c>default</c>.</item>
+ <item>If Gt is <c>Gt_1 Op Gt_2</c>, where <c>Op</c>
+ is a binary operator, then Rep(Gt) =
+ <c>{op,LINE,Op,Rep(Gt_1),Rep(Gt_2)}</c>.</item>
+ <item>If Gt is <c>Op Gt_0</c>, where <c>Op</c> is a unary operator, then
+ Rep(Gt) = <c>{op,LINE,Op,Rep(Gt_0)}</c>.</item>
+ <item>If Gt is <c>#Name{Field_1=Gt_1, ..., Field_k=Gt_k}</c>, then
Rep(E) =
- <c><![CDATA[{record,LINE,Name,[{record_field,LINE,Rep(Field_1),Rep(Gt_1)}, ..., {record_field,LINE,Rep(Field_k),Rep(Gt_k)}]}]]></c>.</item>
- <item>If Gt is <c><![CDATA[#Name.Field]]></c>, then
- Rep(Gt) = <c><![CDATA[{record_index,LINE,Name,Rep(Field)}]]></c>.</item>
- <item>If Gt is <c><![CDATA[Gt_0#Name.Field]]></c>, then
- Rep(Gt) = <c><![CDATA[{record_field,LINE,Rep(Gt_0),Name,Rep(Field)}]]></c>.</item>
- <item>If Gt is <c><![CDATA[A(Gt_1, ..., Gt_k)]]></c>, where <c><![CDATA[A]]></c> is an atom, then
- Rep(Gt) = <c><![CDATA[{call,LINE,Rep(A),[Rep(Gt_1), ..., Rep(Gt_k)]}]]></c>.</item>
- <item>If Gt is <c><![CDATA[A_m:A(Gt_1, ..., Gt_k)]]></c>, where <c><![CDATA[A_m]]></c> is
- the atom <c><![CDATA[erlang]]></c> and <c><![CDATA[A]]></c> is an atom or an operator, then
- Rep(Gt) = <c><![CDATA[{call,LINE,{remote,LINE,Rep(A_m),Rep(A)},[Rep(Gt_1), ..., Rep(Gt_k)]}]]></c>.</item>
- <item>If Gt is <c><![CDATA[{A_m,A}(Gt_1, ..., Gt_k)]]></c>, where <c><![CDATA[A_m]]></c> is
- the atom <c><![CDATA[erlang]]></c> and <c><![CDATA[A]]></c> is an atom or an operator, then
- Rep(Gt) = <c><![CDATA[{call,LINE,Rep({A_m,A}),[Rep(Gt_1), ..., Rep(Gt_k)]}]]></c>.</item>
- <item>If Gt is <c><![CDATA[( Gt_0 )]]></c>, then
- Rep(Gt) = <c><![CDATA[Rep(Gt_0)]]></c>, that is, parenthesized
+ <c>{record,LINE,Name,[{record_field,LINE,Rep(Field_1),Rep(Gt_1)}, ..., {record_field,LINE,Rep(Field_k),Rep(Gt_k)}]}</c>.</item>
+ <item>If Gt is <c>#Name.Field</c>, then
+ Rep(Gt) = <c>{record_index,LINE,Name,Rep(Field)}</c>.</item>
+ <item>If Gt is <c>Gt_0#Name.Field</c>, then
+ Rep(Gt) = <c>{record_field,LINE,Rep(Gt_0),Name,Rep(Field)}</c>.</item>
+ <item>If Gt is <c>A(Gt_1, ..., Gt_k)</c>, where <c>A</c> is an atom, then
+ Rep(Gt) = <c>{call,LINE,Rep(A),[Rep(Gt_1), ..., Rep(Gt_k)]}</c>.</item>
+ <item>If Gt is <c>A_m:A(Gt_1, ..., Gt_k)</c>, where <c>A_m</c> is
+ the atom <c>erlang</c> and <c>A</c> is an atom or an operator, then
+ Rep(Gt) = <c>{call,LINE,{remote,LINE,Rep(A_m),Rep(A)},[Rep(Gt_1), ..., Rep(Gt_k)]}</c>.</item>
+ <item>If Gt is <c>{A_m,A}(Gt_1, ..., Gt_k)</c>, where <c>A_m</c> is
+ the atom <c>erlang</c> and <c>A</c> is an atom or an operator, then
+ Rep(Gt) = <c>{call,LINE,Rep({A_m,A}),[Rep(Gt_1), ..., Rep(Gt_k)]}</c>.
+ </item>
+ <item>If Gt is <c>( Gt_0 )</c>, then
+ Rep(Gt) = <c>Rep(Gt_0)</c>, that is, parenthesized
guard tests cannot be distinguished from their bodies.</item>
</list>
<p>Note that every guard test has the same source form as some expression,
@@ -599,18 +596,18 @@
<section>
<title>The Abstract Format After Preprocessing</title>
- <p>The compilation option <c><![CDATA[debug_info]]></c> can be given to the
- compiler to have the abstract code stored in
- the <c><![CDATA[abstract_code]]></c> chunk in the BEAM file
+ <p>The compilation option <c>debug_info</c> can be given to the
+ compiler to have the abstract code stored in
+ the <c>abstract_code</c> chunk in the BEAM file
(for debugging purposes).</p>
- <p>In OTP R9C and later, the <c><![CDATA[abstract_code]]></c> chunk will
+ <p>In OTP R9C and later, the <c>abstract_code</c> chunk will
contain</p>
- <p><c><![CDATA[{raw_abstract_v1,AbstractCode}]]></c></p>
- <p>where <c><![CDATA[AbstractCode]]></c> is the abstract code as described
+ <p><c>{raw_abstract_v1,AbstractCode}</c></p>
+ <p>where <c>AbstractCode</c> is the abstract code as described
in this document.</p>
<p>In releases of OTP prior to R9C, the abstract code after some more
processing was stored in the BEAM file. The first element of the
- tuple would be either <c><![CDATA[abstract_v1]]></c> (R7B) or <c><![CDATA[abstract_v2]]></c>
+ tuple would be either <c>abstract_v1</c> (R7B) or <c>abstract_v2</c>
(R8B).</p>
</section>
</chapter>