diff options
Diffstat (limited to 'system/doc/reference_manual')
| -rw-r--r-- | system/doc/reference_manual/Makefile | 4 | ||||
| -rw-r--r-- | system/doc/reference_manual/errors.xml | 47 | ||||
| -rw-r--r-- | system/doc/reference_manual/expressions.xml | 38 | ||||
| -rw-r--r-- | system/doc/reference_manual/introduction.xml | 4 | ||||
| -rw-r--r-- | system/doc/reference_manual/macros.xml | 37 | ||||
| -rw-r--r-- | system/doc/reference_manual/modules.xml | 8 | ||||
| -rw-r--r-- | system/doc/reference_manual/typespec.xml | 26 | ||||
| -rw-r--r-- | system/doc/reference_manual/xmlfiles.mk | 2 |
8 files changed, 139 insertions, 27 deletions
diff --git a/system/doc/reference_manual/Makefile b/system/doc/reference_manual/Makefile index e14a056979..d034ad2ff8 100644 --- a/system/doc/reference_manual/Makefile +++ b/system/doc/reference_manual/Makefile @@ -1,7 +1,7 @@ # # %CopyrightBegin% # -# Copyright Ericsson AB 2003-2016. All Rights Reserved. +# Copyright Ericsson AB 2003-2018. All Rights Reserved. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. @@ -28,6 +28,7 @@ include $(ERL_TOP)/erts/vsn.mk #VSN=$(SYSTEM_VSN) APPLICATION=otp-system-documentation +XMLDIR := $(XMLDIR)/reference_manual # ---------------------------------------------------- # Release directory specification # ---------------------------------------------------- @@ -95,6 +96,7 @@ debug opt: clean clean_docs: rm -rf $(HTMLDIR) + rm -rf $(XMLDIR) rm -f $(TOP_PDF_FILE) $(TOP_PDF_FILE:%.pdf=%.fo) rm -f errs core *~ diff --git a/system/doc/reference_manual/errors.xml b/system/doc/reference_manual/errors.xml index b16c5da6eb..16d3e7590e 100644 --- a/system/doc/reference_manual/errors.xml +++ b/system/doc/reference_manual/errors.xml @@ -108,14 +108,55 @@ (see <seealso marker="#exit_reasons">Exit Reason</seealso>), and a stack trace (which aids in finding the code location of the exception).</p> - <p>The stack trace can be retrieved using - <c>erlang:get_stacktrace/0</c> - from within a <c>try</c> expression, and is returned for + <p>The stack trace can be be bound to a variable from within + a <c>try</c> expression, and is returned for exceptions of class <c>error</c> from a <c>catch</c> expression.</p> <p>An exception of class <c>error</c> is also known as a run-time error.</p> + + <section> + <title>The call-stack back trace (stacktrace)</title> + <p>The stack back-trace (<em>stacktrace</em>) is a list of + <c>{Module,Function,Arity,Location}</c> + tuples. The field <c>Arity</c> in the first tuple can be the + argument list of that function call instead of an arity integer, + depending on the exception.</p> + + <p><c>Location</c> is a (possibly empty) list of two-tuples + that can indicate the location in the source code of the + function. The first element is an atom describing the type of + information in the second element. The following items can + occur:</p> + <taglist> + <tag><c>file</c></tag> + <item>The second element of the tuple is a string (list of + characters) representing the filename of the source file + of the function. + </item> + <tag><c>line</c></tag> + <item>The second element of the tuple is the line number + (an integer > 0) in the source file + where the exception occurred or the function was called. + </item> + </taglist> + <warning><p>Developers should rely on stacktrace entries only for + debugging purposes.</p> + <p>The VM performs tail call optimization, which + does not add new entries to the stacktrace, and also limits stacktraces + to a certain depth. Furthermore, compiler options, optimizations and + future changes may add or remove stacktrace entries, causing any code + that expects the stacktrace to be in a certain order or contain specific + items to fail.</p> + <p>The only exception to this rule is the class <c>error</c> with the + reason <c>undef</c> which is guaranteed to include the <c>Module</c>, + <c>Function</c> and <c>Arity</c> of the attempted + function as the first stacktrace entry.</p> + </warning> + </section> + </section> + <section> <title>Handling of Run-time Errors in Erlang</title> diff --git a/system/doc/reference_manual/expressions.xml b/system/doc/reference_manual/expressions.xml index cf2d5034aa..76b3e92937 100644 --- a/system/doc/reference_manual/expressions.xml +++ b/system/doc/reference_manual/expressions.xml @@ -4,7 +4,7 @@ <chapter> <header> <copyright> - <year>2003</year><year>2017</year> + <year>2003</year><year>2018</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> @@ -567,6 +567,10 @@ Expr1 <input>op</input> Expr2</pre> order is defined:</p> <pre> number < atom < reference < fun < port < pid < tuple < map < nil < list < bit string</pre> + <p><c>nil</c> in the previous expression represents the empty list + (<c>[]</c>), which is regarded as a separate type from + <c>list/0</c>. That is why <c>nil < list</c>. + </p> <p>Lists are compared element by element. Tuples are ordered by size, two tuples with the same size are compared element by element.</p> @@ -1340,9 +1344,9 @@ hello</pre> <code type="none"> try Exprs catch - [Class1:]ExceptionPattern1 [when ExceptionGuardSeq1] -> + Class1:ExceptionPattern1[:Stacktrace] [when ExceptionGuardSeq1] -> ExceptionBody1; - [ClassN:]ExceptionPatternN [when ExceptionGuardSeqN] -> + ClassN:ExceptionPatternN[:Stacktrace] [when ExceptionGuardSeqN] -> ExceptionBodyN end</code> <p>This is an enhancement of @@ -1362,10 +1366,12 @@ end</code> the evaluation. In that case the exception is caught and the patterns <c>ExceptionPattern</c> with the right exception class <c>Class</c> are sequentially matched against the caught - exception. An omitted <c>Class</c> is shorthand for <c>throw</c>. - If a match succeeds and the optional guard sequence + exception. If a match succeeds and the optional guard sequence <c>ExceptionGuardSeq</c> is true, the corresponding <c>ExceptionBody</c> is evaluated to become the return value.</p> + <p><c>Stacktrace</c>, if specified, must be the name of a variable + (not a pattern). The stack trace is bound to the variable when + the corresponding <c>ExceptionPattern</c> matches.</p> <p>If an exception occurs during evaluation of <c>Exprs</c> but there is no matching <c>ExceptionPattern</c> of the right <c>Class</c> with a true guard sequence, the exception is passed @@ -1373,6 +1379,18 @@ end</code> expression.</p> <p>If an exception occurs during evaluation of <c>ExceptionBody</c>, it is not caught.</p> + <p>It is allowed to omit <c>Class</c> and <c>Stacktrace</c>. + An omitted <c>Class</c> is shorthand for <c>throw</c>:</p> + + <code type="none"> +try Exprs +catch + ExceptionPattern1 [when ExceptionGuardSeq1] -> + ExceptionBody1; + ExceptionPatternN [when ExceptionGuardSeqN] -> + ExceptionBodyN +end</code> + <p>The <c>try</c> expression can have an <c>of</c> section: </p> @@ -1384,10 +1402,10 @@ try Exprs of PatternN [when GuardSeqN] -> BodyN catch - [Class1:]ExceptionPattern1 [when ExceptionGuardSeq1] -> + Class1:ExceptionPattern1[:Stacktrace] [when ExceptionGuardSeq1] -> ExceptionBody1; ...; - [ClassN:]ExceptionPatternN [when ExceptionGuardSeqN] -> + ClassN:ExceptionPatternN[:Stacktrace] [when ExceptionGuardSeqN] -> ExceptionBodyN end</code> <p>If the evaluation of <c>Exprs</c> succeeds without an exception, @@ -1408,10 +1426,10 @@ try Exprs of PatternN [when GuardSeqN] -> BodyN catch - [Class1:]ExceptionPattern1 [when ExceptionGuardSeq1] -> + Class1:ExceptionPattern1[:Stacktrace] [when ExceptionGuardSeq1] -> ExceptionBody1; ...; - [ClassN:]ExceptionPatternN [when ExceptionGuardSeqN] -> + ClassN:ExceptionPatternN[:Stacktrace] [when ExceptionGuardSeqN] -> ExceptionBodyN after AfterBody @@ -1470,7 +1488,7 @@ try Expr catch throw:Term -> Term; exit:Reason -> {'EXIT',Reason} - error:Reason -> {'EXIT',{Reason,erlang:get_stacktrace()}} + error:Reason:Stk -> {'EXIT',{Reason,Stk}} end</code> </section> diff --git a/system/doc/reference_manual/introduction.xml b/system/doc/reference_manual/introduction.xml index afbdfa7434..69e52e0b37 100644 --- a/system/doc/reference_manual/introduction.xml +++ b/system/doc/reference_manual/introduction.xml @@ -4,7 +4,7 @@ <chapter> <header> <copyright> - <year>2003</year><year>2017</year> + <year>2003</year><year>2018</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> @@ -48,7 +48,7 @@ System Principles</seealso></p> <p>Starting and stopping, boot scripts, code loading, <seealso marker="doc/system_principles:error_logging"> - error logging</seealso>, + logging</seealso>, <seealso marker="doc/system_principles:create_target"> creating target systems</seealso></p> </item> diff --git a/system/doc/reference_manual/macros.xml b/system/doc/reference_manual/macros.xml index a341307ab7..8a8d5f3a4c 100644 --- a/system/doc/reference_manual/macros.xml +++ b/system/doc/reference_manual/macros.xml @@ -4,7 +4,7 @@ <chapter> <header> <copyright> - <year>2003</year><year>2017</year> + <year>2003</year><year>2018</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> @@ -150,6 +150,11 @@ bar(X) -> <item>The name of the current function.</item> <tag><c>?FUNCTION_ARITY</c></tag> <item>The arity (number of arguments) for the current function.</item> + <tag><c>?OTP_RELEASE</c></tag> + <item>The OTP release that the currently executing ERTS + application is part of, as an integer. For details, see + <seealso marker="erts:erlang#system_info/1"><c>erlang:system_info(otp_release)</c></seealso>. + This macro was introduced in OTP release 21.</item> </taglist> </section> @@ -202,8 +207,16 @@ f() -> directive. If that condition is false, the lines following <c>else</c> are evaluated instead.</item> <tag><c>-endif.</c></tag> - <item>Specifies the end of an <c>ifdef</c> or <c>ifndef</c> - directive.</item> + <item>Specifies the end of an <c>ifdef</c>, an <c>ifndef</c> + directive, or the end of an <c>if</c> or <c>elif</c> directive.</item> + <tag><c>-if(Condition).</c></tag> + <item>Evaluates the following lines only if <c>Condition</c> + evaluates to true.</item> + <tag><c>-elif(Condition).</c></tag> + <item>Only allowed after an <c>if</c> or another <c>elif</c> directive. + If the preceding <c>if</c> or <c>elif</c> directives do not + evaluate to true, and the <c>Condition</c> evaluates to true, + the lines following the <c>elif</c> are evaluated instead.</item> </taglist> <note> <p>The macro directives cannot be used inside functions.</p> @@ -231,6 +244,24 @@ or {ok,m}</pre> <p><c>?LOG(Arg)</c> is then expanded to a call to <c>io:format/2</c> and provide the user with some simple trace output.</p> + + <p><em>Example:</em></p> + <code type="none"> +-module(m) +... +-ifdef(OTP_RELEASE). + %% OTP 21 or higher + -if(?OTP_RELEASE >= 22). + %% Code that will work in OTP 22 or higher + -elif(?OTP_RELEASE >= 21). + %% Code that will work in OTP 21 or higher + -endif. +-else. + %% OTP 20 or lower. +-endif. +...</code> + <p>The code uses the <c>OTP_RELEASE</c> macro to conditionally + select code depending on release.</p> </section> <section> diff --git a/system/doc/reference_manual/modules.xml b/system/doc/reference_manual/modules.xml index 4a97bfeb7b..6f93198ec1 100644 --- a/system/doc/reference_manual/modules.xml +++ b/system/doc/reference_manual/modules.xml @@ -4,7 +4,7 @@ <chapter> <header> <copyright> - <year>2003</year><year>2017</year> + <year>2003</year><year>2018</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> @@ -307,6 +307,12 @@ behaviour_info(callbacks) -> Callbacks.</pre> all functions in the module.</p> </item> + <tag><c>nifs</c></tag> + <item> + <p>Returns a list of <c>{Name,Arity}</c> tuples with + all NIF functions in the module.</p> + </item> + <tag><c>native</c></tag> <item> <p>Return <c>true</c> if the module has native compiled code. diff --git a/system/doc/reference_manual/typespec.xml b/system/doc/reference_manual/typespec.xml index f6a19397c3..27cd0ba83d 100644 --- a/system/doc/reference_manual/typespec.xml +++ b/system/doc/reference_manual/typespec.xml @@ -4,7 +4,7 @@ <chapter> <header> <copyright> - <year>2003</year><year>2017</year> + <year>2003</year><year>2018</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> @@ -113,8 +113,8 @@ | Erlang_Atom %% 'foo', 'bar', ... Bitstring :: <<>> - | <<_:M>> %% M is a positive integer - | <<_:_*N>> %% N is a positive integer + | <<_:M>> %% M is an Integer_Value that evaluates to a positive integer + | <<_:_*N>> %% N is an Integer_Value that evaluates to a positive integer | <<_:M, _:_*N>> Fun :: fun() %% any function @@ -123,8 +123,17 @@ | fun((TList) -> Type) Integer :: integer() - | Erlang_Integer %% ..., -1, 0, 1, ... 42 ... - | Erlang_Integer..Erlang_Integer %% specifies an integer range + | Integer_Value + | Integer_Value..Integer_Value %% specifies an integer range + + Integer_Value :: Erlang_Integer %% ..., -1, 0, 1, ... 42 ... + | Erlang_Character %% $a, $b ... + | Integer_Value BinaryOp Integer_Value + | UnaryOp Integer_Value + + BinaryOp :: '*' | 'div' | 'rem' | 'band' | '+' | '-' | 'bor' | 'bxor' | 'bsl' | 'bsr' + + UnaryOp :: '+' | '-' | 'bnot' List :: list(Type) %% Proper list ([]-terminated) | maybe_improper_list(Type1, Type2) %% Type1=contents, Type2=termination @@ -151,8 +160,13 @@ Union :: Type1 | Type2 ]]></pre> <p> + Integer values are either integer or character literals or expressions + consisting of possibily nested unary or binary operations that evaluate to + an integer. Such expressions can also be used in bit strings and ranges. + </p> + <p> The general form of bit strings is <c><<_:M, _:_*N>></c>, - where <c>M</c> and <c>N</c> are positive integers. It denotes a + where <c>M</c> and <c>N</c> must evaluate to positive integers. It denotes a bit string that is <c>M + (k*N)</c> bits long (that is, a bit string that starts with <c>M</c> bits and continues with <c>k</c> segments of <c>N</c> bits each, where <c>k</c> is also a positive integer). diff --git a/system/doc/reference_manual/xmlfiles.mk b/system/doc/reference_manual/xmlfiles.mk index fffcbdd911..92d232b628 100644 --- a/system/doc/reference_manual/xmlfiles.mk +++ b/system/doc/reference_manual/xmlfiles.mk @@ -1,7 +1,7 @@ # # %CopyrightBegin% # -# Copyright Ericsson AB 2009-2016. All Rights Reserved. +# Copyright Ericsson AB 2009-2018. All Rights Reserved. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. |