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authorHans Bolinder <[email protected]>2016-01-20 09:55:21 +0100
committerHans Bolinder <[email protected]>2016-01-20 10:26:03 +0100
commit6e2d941bf278191c11f6d1cebdfab5e51419d734 (patch)
tree39b57bb43a713af23b36c5297c7a795bff425a08 /erts/doc
parent34e02fed50bbaa2af7b1828968b6ec02a54e98c8 (diff)
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erts: Improve readability of The Abstract Format
More verbose, but hopefully more readable than before.
Diffstat (limited to 'erts/doc')
-rw-r--r--erts/doc/src/absform.xml420
1 files changed, 228 insertions, 192 deletions
diff --git a/erts/doc/src/absform.xml b/erts/doc/src/absform.xml
index 3f47b3061b..ccdecf44ec 100644
--- a/erts/doc/src/absform.xml
+++ b/erts/doc/src/absform.xml
@@ -68,34 +68,29 @@
<item>If D is a module declaration consisting of the forms
<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>-compile(Options)</c>, then
+ Rep(F) = <c>{attribute,LINE,compile,Options}</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>-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>-module(Mod)</c>, then
+ Rep(F) = <c>{attribute,LINE,module,Mod}</c>.</item>
<item>If F is an attribute <c>-optional_callbacks([Fun_1/A_1, ..., Fun_k/A_k])</c>, then
Rep(F) = <c>{attribute,LINE,optional_callbacks,[{Fun_1,A_1}, ..., {Fun_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>,
- where each <c>V_i</c> is a record field, then Rep(F) =
- <c>{attribute,LINE,record,{Name,[Rep(V_1), ..., Rep(V_k)]}}</c>.
- For Rep(V), see below.</item>
- <item>If F is a type declaration
- <c>-Type Name(V_1, ..., V_k) :: T</c>, where
- <c>Type</c> is either the atom <c>type</c> or the atom <c>opaque</c>,
- each <c>V_i</c> is a variable, and <c>T</c> is a type, then Rep(F) =
- <c>{attribute,LINE,Type,{Name,Rep(T),[Rep(V_1), ..., Rep(V_k)]}}</c>.
+ <item>If F is a function declaration
+ <c>Name Fc_1 ; ... ; Name Fc_k</c>,
+ where each <c>Fc_i</c> is a function clause with a
+ pattern sequence of the same length <c>Arity</c>, then
+ Rep(F) = <c>{function,LINE,Name,Arity,[Rep(Fc_1), ...,Rep(Fc_k)]}</c>.
</item>
<item>If F is a function specification
<c>-Spec Name Ft_1; ...; Ft_k</c>,
@@ -112,15 +107,20 @@
<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 record declaration
+ <c>-record(Name,{V_1, ..., V_k})</c>,
+ where each <c>V_i</c> is a record field, then Rep(F) =
+ <c>{attribute,LINE,record,{Name,[Rep(V_1), ..., Rep(V_k)]}}</c>.
+ For Rep(V), see below.</item>
+ <item>If F is a type declaration
+ <c>-Type Name(V_1, ..., V_k) :: T</c>, where
+ <c>Type</c> is either the atom <c>type</c> or the atom <c>opaque</c>,
+ each <c>V_i</c> is a variable, and <c>T</c> is a type, then Rep(F) =
+ <c>{attribute,LINE,Type,{Name,Rep(T),[Rep(V_1), ..., Rep(V_k)]}}</c>.
+ </item>
<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>,
- where each <c>Fc_i</c> is a function clause with a
- pattern sequence of the same length <c>Arity</c>, then
- Rep(F) = <c>{function,LINE,Name,Arity,[Rep(Fc_1), ...,Rep(Fc_k)]}</c>.
- </item>
</list>
<section>
@@ -160,15 +160,15 @@
<p>There are five kinds of atomic literals, which are represented in the
same way in patterns, expressions and guards:</p>
<list type="bulleted">
- <item>If L is an integer or character literal, then
- Rep(L) = <c>{integer,LINE,L}</c>.</item>
+ <item>If L is an atom literal, then
+ Rep(L) = <c>{atom,LINE,L}</c>.</item>
<item>If L is a float literal, then
Rep(L) = <c>{float,LINE,L}</c>.</item>
+ <item>If L is an integer or character literal, then
+ Rep(L) = <c>{integer,LINE,L}</c>.</item>
<item>If L is a string literal consisting of the characters
<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>{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>
@@ -182,45 +182,53 @@
<p>Individual patterns are represented as follows:</p>
<list type="bulleted">
<item>If P is an atomic literal <c>L</c>, then Rep(P) = Rep(L).</item>
+ <item>If P is a binary pattern
+ <c>&lt;&lt;P_1:Size_1/TSL_1, ..., P_k:Size_k/TSL_k>></c>, where each
+ <c>Size_i</c> is an expression that can be evaluated to an integer
+ and each <c>TSL_i</c> is a type specificer list, then
+ Rep(P) = <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>Size_i</c> is represented by <c>default</c>.
+ An omitted <c>TSL_i</c> is represented by <c>default</c>.</item>
<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>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>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>{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>{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>{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 a map pattern <c>#{A_1, ..., A_k}</c>, where each
<c>A_i</c> is an association <c>P_i_1 := P_i_2</c>, then Rep(P) =
<c>{map,LINE,[Rep(A_1), ..., Rep(A_k)]}</c>. For Rep(A), see
below.</item>
- <item>If P is <c>( P_0 )</c>, then
+ <item>If P is a nil pattern <c>[]</c>, then
+ Rep(P) = <c>{nil,LINE}</c>.</item>
+ <item>If P is an operator pattern <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>{op,LINE,Op,Rep(P_1),Rep(P_2)}</c>.</item>
+ <item>If P is an operator pattern <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>{op,LINE,Op,Rep(P_0)}</c>.</item>
+ <item>If P is a parenthesized pattern <c>( P_0 )</c>, then
Rep(P) = <c>Rep(P_0)</c>,
- that is, patterns cannot be distinguished from their bodies.</item>
+ that is, parenthesized patterns cannot be distinguished from their
+ bodies.</item>
+ <item>If P is a record field index pattern <c>#Name.Field</c>,
+ where <c>Field</c> is an atom, then
+ Rep(P) = <c>{record_index,LINE,Name,Rep(Field)}</c>.</item>
+ <item>If P is a record pattern
+ <c>#Name{Field_1=P_1, ..., Field_k=P_k}</c>,
+ where each <c>Field_i</c> is an atom or <c>_</c>, then Rep(P) =
+ <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 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 universal pattern <c>_</c>, then
+ Rep(P) = <c>{var,LINE,'_'}</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>V</c>.</item>
</list>
<p>Note that every pattern has the same source form as some expression, and is
represented the same way as the corresponding expression.</p>
@@ -233,36 +241,58 @@
<p>An expression E is one of the following alternatives:</p>
<list type="bulleted">
<item>If E is an atomic literal <c>L</c>, then Rep(E) = 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 binary comprehension
+ <c>&lt;&lt;E_0 || Q_1, ..., Q_k>></c>,
+ where each <c>Q_i</c> is a qualifier, then
+ Rep(E) = <c>{bc,LINE,Rep(E_0),[Rep(Q_1), ..., Rep(Q_k)]}</c>.
+ For Rep(Q), see below.</item>
+ <item>If E is a binary constructor <c>&lt;&lt;E_1:Size_1/TSL_1, ..., E_k:Size_k/TSL_k>></c>,
+ where each <c>Size_i</c> is an expression and each
+ <c>TSL_i</c> is a type specificer list, then Rep(E) =
+ <c>{bin,LINE,[{bin_element,LINE,Rep(E_1),Rep(Size_1),Rep(TSL_1)}, ..., {bin_element,LINE,Rep(E_k),Rep(Size_k),Rep(TSL_k)}]}</c>.
+ For Rep(TSL), see below.
+ An omitted <c>Size_i</c> is represented by <c>default</c>.
+ An omitted <c>TSL_i</c> is represented by <c>default</c>.</item>
+ <item>If E is a block expression <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 a case expression <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 a catch expression <c>catch E_0</c>, then
+ Rep(E) = <c>{'catch',LINE,Rep(E_0)}</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>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>,
+ <item>If E is a fun expression <c>fun Name/Arity</c>, then
+ Rep(E) = <c>{'fun',LINE,{function,Name,Arity}}</c>.</item>
+ <item>If E is a fun expression
+ <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 a fun expression <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 a fun expression
+ <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 a function call <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 a function call <c>E_m:E_0(E_1, ..., 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>{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>
+ <c>{call,LINE,{remote,LINE,Rep(E_m),Rep(E_0)},[Rep(E_1), ..., Rep(E_k)]}</c>.
+ </item>
+ <item>If E is an if expression <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 a list comprehension <c>[E_0 || Q_1, ..., Q_k]</c>,
+ where each <c>Q_i</c> is a qualifier, then Rep(E) =
+ <c>{lc,LINE,Rep(E_0),[Rep(Q_1), ..., Rep(Q_k)]}</c>. For Rep(Q), see
+ below.</item>
<item>If E is a map creation <c>#{A_1, ..., A_k}</c>,
where each <c>A_i</c> is an association <c>E_i_1 => E_i_2</c>
or <c>E_i_1 := E_i_2</c>, then Rep(E) =
@@ -273,95 +303,92 @@
or <c>E_i_1 := E_i_2</c>, then Rep(E) =
<c>{map,LINE,Rep(E_0),[Rep(A_1), ..., Rep(A_k)]}</c>.
For Rep(A), 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 || Q_1, ..., Q_k]</c>,
- where each <c>Q_i</c> is a qualifier, then Rep(E) =
- <c>{lc,LINE,Rep(E_0),[Rep(Q_1), ..., Rep(Q_k)]}</c>. For Rep(Q), see
- below.</item>
- <item>If E is a binary comprehension
- <c>&lt;&lt;E_0 || Q_1, ..., Q_k>></c>,
- where each <c>Q_i</c> is a qualifier, then
- Rep(E) = <c>{bc,LINE,Rep(E_0),[Rep(Q_1), ..., Rep(Q_k)]}</c>.
- For Rep(Q), 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>,
+ <item>If E is a match operator expression <c>P = E_0</c>,
+ where <c>P</c> is a pattern, then
+ Rep(E) = <c>{match,LINE,Rep(P),Rep(E_0)}</c>.</item>
+ <item>If E is nil, <c>[]</c>, then
+ Rep(E) = <c>{nil,LINE}</c>.</item>
+ <item>If E is an operator expression <c>E_1 Op E_2</c>,
+ where <c>Op</c> is a binary operator other than the match
+ operator <c>=</c>, then
+ Rep(E) = <c>{op,LINE,Op,Rep(E_1),Rep(E_2)}</c>.</item>
+ <item>If E is an operator expression <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 a parenthesized expression <c>( E_0 )</c>, then
+ Rep(E) = <c>Rep(E_0)</c>, that is, parenthesized
+ expressions cannot be distinguished from their bodies.</item>
+ <item>If E is a receive expression <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 a receive expression
+ <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 a record creation
+ <c>#Name{Field_1=E_1, ..., Field_k=E_k}</c>,
+ where each <c>Field_i</c> is an atom or <c>_</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 a record field access <c>E_0#Name.Field</c>,
+ where <c>Field</c> is an atom, then
+ Rep(E) = <c>{record_field,LINE,Rep(E_0),Name,Rep(Field)}</c>.</item>
+ <item>If E is a record field index <c>#Name.Field</c>,
+ where <c>Field</c> is an atom, then
+ Rep(E) = <c>{record_index,LINE,Name,Rep(Field)}</c>.</item>
+ <item>If E is a record update
+ <c>E_0#Name{Field_1=E_1, ..., Field_k=E_k}</c>,
+ where each <c>Field_i</c> is an atom, then Rep(E) =
+ <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 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 a try expression <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>{'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>,
+ <item>If E is a try expression
+ <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>,
+ <item>If E is a try expression <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>,
+ <item>If E is a try expression
+ <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>,
+ <item>If E is a try expression
+ <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>,
+ <item>If E is a try expression
+ <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>{'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>( E_0 )</c>, then
- Rep(E) = <c>Rep(E_0)</c>, that is, parenthesized
- expressions cannot be distinguished from their bodies.</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>
</list>
<section>
<title>Qualifiers</title>
<p>A qualifier Q is one of the following alternatives:</p>
<list type="bulleted">
+ <item>If Q is a filter <c>E</c>, where <c>E</c> is an expression, then
+ Rep(Q) = <c>Rep(E)</c>.</item>
<item>If Q is a generator <c>P &lt;- E</c>, where <c>P</c> is
a pattern and <c>E</c> is an expression, then
Rep(Q) = <c>{generate,LINE,Rep(P),Rep(E)}</c>.</item>
<item>If Q is a generator <c>P &lt;= E</c>, where <c>P</c> is
a pattern and <c>E</c> is an expression, then
Rep(Q) = <c>{b_generate,LINE,Rep(P),Rep(E)}</c>.</item>
- <item>If Q is a filter <c>E</c>, where <c>E</c> is an expression, then
- Rep(Q) = <c>Rep(E)</c>.</item>
</list>
</section>
@@ -399,16 +426,6 @@
and catch clauses.</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>( 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>
@@ -432,6 +449,16 @@
<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>
+ <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>
</list>
</section>
@@ -446,33 +473,23 @@
<p>A guard test <c>Gt</c> is one of the following alternatives:</p>
<list type="bulleted">
<item>If Gt is an atomic literal <c>L</c>, then Rep(Gt) = Rep(L).</item>
- <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
+ <c>&lt;&lt;Gt_1:Size_1/TSL_1, ..., Gt_k:Size_k/TSL_k>></c>,
+ where each <c>Size_i</c> is a guard test and each
+ <c>TSL_i</c> is a type specificer list, 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>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>{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>
+ An omitted <c>Size_i</c> is represented by <c>default</c>.
+ An omitted <c>TSL_i</c> is represented by <c>default</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 function call <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 a function call <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 a map creation <c>#{A_1, ..., A_k}</c>,
where each <c>A_i</c> is an association <c>Gt_i_1 => Gt_i_2</c>
or <c>Gt_i_1 := Gt_i_2</c>, then Rep(Gt) =
@@ -483,14 +500,33 @@
or <c>Gt_i_1 := Gt_i_2</c>, then Rep(Gt) =
<c>{map,LINE,Rep(Gt_0),[Rep(A_1), ..., Rep(A_k)]}</c>.
For Rep(A), see above.</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>( Gt_0 )</c>, then
+ <item>If Gt is nil, <c>[]</c>,
+ then Rep(Gt) = <c>{nil,LINE}</c>.</item>
+ <item>If Gt is an operator guard test <c>Gt_1 Op Gt_2</c>,
+ where <c>Op</c> is a binary operator other than the match
+ operator <c>=</c>, then
+ Rep(Gt) = <c>{op,LINE,Op,Rep(Gt_1),Rep(Gt_2)}</c>.</item>
+ <item>If Gt is an operator guard test <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 a parenthesized guard test <c>( Gt_0 )</c>, then
Rep(Gt) = <c>Rep(Gt_0)</c>, that is, parenthesized
guard tests cannot be distinguished from their bodies.</item>
+ <item>If Gt is a record creation
+ <c>#Name{Field_1=Gt_1, ..., Field_k=Gt_k}</c>,
+ where each <c>Field_i</c> is an atom or <c>_</c>, then Rep(Gt) =
+ <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 a record field access <c>Gt_0#Name.Field</c>,
+ where <c>Field</c> is an atom, then
+ Rep(Gt) = <c>{record_field,LINE,Rep(Gt_0),Name,Rep(Field)}</c>.</item>
+ <item>If Gt is a record field index <c>#Name.Field</c>,
+ where <c>Field</c> is an atom, then
+ Rep(Gt) = <c>{record_index,LINE,Name,Rep(Field)}</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 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>
</list>
<p>Note that every guard test has the same source form as some expression,
and is represented the same way as the corresponding expression.</p>
@@ -504,15 +540,6 @@
<c>{ann_type,LINE,[Rep(A),Rep(T_0)]}</c>.</item>
<item>If T is an atom or integer literal L, then Rep(T) = Rep(L).
</item>
- <item>If T is an operator type <c>T_1 Op T_2</c>,
- where <c>Op</c> is a binary operator (this is an occurrence of
- an expression that can be evaluated to an integer at compile
- time), then
- Rep(T) = <c>{op,LINE,Op,Rep(T_1),Rep(T_2)}</c>.</item>
- <item>If T is an operator type <c>Op T_0</c>, where <c>Op</c> is a
- unary operator (this is an occurrence of
- an expression that can be evaluated to an integer at compile time),
- then Rep(T) = <c>{op,LINE,Op,Rep(T_0)}</c>.</item>
<item>If T is a bitstring type <c>&lt;&lt;_:M,_:_*N>></c>,
where <c>M</c> and <c>N</c> are singleton integer types, then Rep(T) =
<c>{type,LINE,binary,[Rep(M),Rep(N)]}</c>.</item>
@@ -535,6 +562,18 @@
<c>A_i</c> is an association type, then Rep(T) =
<c>{type,LINE,map,[Rep(A_1), ..., Rep(A_k)]}</c>.
For Rep(A), see below.</item>
+ <item>If T is an operator type <c>T_1 Op T_2</c>,
+ where <c>Op</c> is a binary operator (this is an occurrence of
+ an expression that can be evaluated to an integer at compile
+ time), then
+ Rep(T) = <c>{op,LINE,Op,Rep(T_1),Rep(T_2)}</c>.</item>
+ <item>If T is an operator type <c>Op T_0</c>, where <c>Op</c> is a
+ unary operator (this is an occurrence of
+ an expression that can be evaluated to an integer at compile time),
+ then Rep(T) = <c>{op,LINE,Op,Rep(T_0)}</c>.</item>
+ <item>If T is <c>( T_0 )</c>, then Rep(T) = <c>Rep(T_0)</c>,
+ that is, parenthesized types cannot be distinguished from their
+ bodies.</item>
<item>If T is a predefined (or built-in) type <c>N(T_1, ..., T_k)</c>,
then Rep(T) =
<c>{type,LINE,N,[Rep(T_1), ..., Rep(T_k)]}</c>.</item>
@@ -558,9 +597,6 @@
<item>If T is a user-defined type <c>N(T_1, ..., T_k)</c>,
then Rep(T) =
<c>{user_type,LINE,N,[Rep(T_1), ..., Rep(T_k)]}</c>.</item>
- <item>If T is <c>( T_0 )</c>, then Rep(T) = <c>Rep(T_0)</c>,
- that is, parenthesized types cannot be distinguished from their
- bodies.</item>
</list>
<section>