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author | Marcus Arendt <[email protected]> | 2015-01-07 16:11:00 +0100 |
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committer | Marcus Arendt <[email protected]> | 2015-01-07 16:11:00 +0100 |
commit | 821d84c5860a9a26185efa19be407796422e3090 (patch) | |
tree | bd68c23e996bea8c5b4a622df52f27dc0d9848e7 /system/doc | |
parent | 4f7edc376ee61238699f68c8721ab23ee56eafee (diff) | |
parent | aee18f309d41691019fc323bd41c5f78be49953b (diff) | |
download | otp-821d84c5860a9a26185efa19be407796422e3090.tar.gz otp-821d84c5860a9a26185efa19be407796422e3090.tar.bz2 otp-821d84c5860a9a26185efa19be407796422e3090.zip |
Merge branch 'maint'
Diffstat (limited to 'system/doc')
-rw-r--r-- | system/doc/getting_started/conc_prog.xml | 16 | ||||
-rw-r--r-- | system/doc/getting_started/records_macros.xml | 2 | ||||
-rw-r--r-- | system/doc/getting_started/robustness.xml | 2 | ||||
-rw-r--r-- | system/doc/getting_started/seq_prog.xml | 43 |
4 files changed, 31 insertions, 32 deletions
diff --git a/system/doc/getting_started/conc_prog.xml b/system/doc/getting_started/conc_prog.xml index 15feaa9044..6c513162c0 100644 --- a/system/doc/getting_started/conc_prog.xml +++ b/system/doc/getting_started/conc_prog.xml @@ -95,7 +95,7 @@ goodbye</pre> the second a "goodbye", the first another "hello" and so forth. But where did the <0.63.0> come from? The return value of a function is of course the return value of the last "thing" in - the function. The last thing in the function <c>start</c> is</p> + the function. The last thing in the function <c>start</c> is:</p> <code type="none"> spawn(tut14, say_something, [goodbye, 3]).</code> <p><c>spawn</c> returns a <em>process identifier</em>, or @@ -166,11 +166,11 @@ Pong_PID = spawn(tut15, pong, [])</code> <c>start</c> now creates another process "ping".</p> <code type="none"> spawn(tut15, ping, [3, Pong_PID]),</code> - <p>this process executes</p> + <p>This process executes:</p> <code type="none"> tut15:ping(3, Pong_PID)</code> <p><0.36.0> is the return value from the <c>start</c> function.</p> - <p>The process "pong" now does:</p> + <p>The process "pong" now does:</p> <code type="none"> receive finished -> @@ -235,7 +235,7 @@ Ping_PID ! pong</code> Pid ! Message</code> <p>I.e. <c>Message</c> (any Erlang term) is sent to the process with identity <c>Pid</c>.</p> - <p>After sending the message <c>pong</c>, to the process "ping", + <p>After sending the message <c>pong</c> to the process "ping", "pong" calls the <c>pong</c> function again, which causes it to get back to the <c>receive</c> again and wait for another message. Now let's look at the process "ping". Recall that it was started @@ -253,7 +253,7 @@ Pong_PID ! {ping, self()},</code> <p><c>self()</c> returns the pid of the process which executes <c>self()</c>, in this case the pid of "ping". (Recall the code for "pong", this will land up in the variable <c>Ping_PID</c> in - the <c>receive</c> previously explained).</p> + the <c>receive</c> previously explained.)</p> <p>"Ping" now waits for a reply from "pong":</p> <code type="none"> receive @@ -364,7 +364,7 @@ pong ! {ping, self()},</code> <c>.erlang.cookie</c> in the directory you get to after executing the command <c>cd</c> without any argument). The <c>.erlang.cookie</c> file should contain one line with - the same atom. For example on Linux or Unix in the OS shell:</p> + the same atom. For example, on Linux or Unix in the OS shell:</p> <pre> $ <input>cd</input> $ <input>cat > .erlang.cookie</input> @@ -373,7 +373,7 @@ $ <input>chmod 400 .erlang.cookie</input></pre> <p>The <c>chmod</c> above make the <c>.erlang.cookie</c> file accessible only by the owner of the file. This is a requirement.</p> <p>When you start an Erlang system which is going to talk to other - Erlang systems, you must give it a name, eg: </p> + Erlang systems, you must give it a name, e.g.: </p> <pre> $ <input>erl -sname my_name</input></pre> <p>We will see more details of this later. If you want to @@ -385,7 +385,7 @@ $ <input>erl -sname my_name</input></pre> IP domain and we can use only the first component of the IP address, if we want to use nodes in different domains we use <c>-name</c> instead, but then all IP address must be given in - full.</p> + full.)</p> <p>Here is the ping pong example modified to run on two separate nodes:</p> <code type="none"> diff --git a/system/doc/getting_started/records_macros.xml b/system/doc/getting_started/records_macros.xml index 76e3d185fb..2922962134 100644 --- a/system/doc/getting_started/records_macros.xml +++ b/system/doc/getting_started/records_macros.xml @@ -284,7 +284,7 @@ server_transfer(From, Name, To, Message, User_List) -> the record is referred to. If you leave out a field when creating a record, it will get the value of the atom undefined. (*manual*)</p> <p>Pattern matching with records is very similar to creating - records. For example inside a <c>case</c> or <c>receive</c>:</p> + records. For example, inside a <c>case</c> or <c>receive</c>:</p> <code type="none"> #message_to{to_name=ToName, message=Message} -></code> <p>is the same as:</p> diff --git a/system/doc/getting_started/robustness.xml b/system/doc/getting_started/robustness.xml index 359ea93275..b97940d388 100644 --- a/system/doc/getting_started/robustness.xml +++ b/system/doc/getting_started/robustness.xml @@ -30,7 +30,7 @@ </header> <p>There are several things which are wrong with the <seealso marker="conc_prog#ex">messenger example</seealso> from - the previous chapter. For example if a node where a user is logged + the previous chapter. For example, if a node where a user is logged on goes down without doing a log off, the user will remain in the server's <c>User_List</c> but the client will disappear thus making it impossible for the user to log on again as the server diff --git a/system/doc/getting_started/seq_prog.xml b/system/doc/getting_started/seq_prog.xml index be43e8d896..699b9487ed 100644 --- a/system/doc/getting_started/seq_prog.xml +++ b/system/doc/getting_started/seq_prog.xml @@ -62,7 +62,7 @@ Eshell V5.9.1 (abort with ^G) (See the chapter <seealso marker="erts:tty">"tty - A command line interface"</seealso> in ERTS User's Guide).</p> <p>(Note: you will find a lot of line numbers given by the shell out of sequence in this tutorial as it was written and the code - tested in several sessions).</p> + tested in several sessions.)</p> <p>Now let's try a more complex calculation.</p> <pre> 2> <input>(42 + 77) * 66 / 3.</input> @@ -115,7 +115,7 @@ double(X) -> entered and there will also be error messages to give you some idea as to what has gone wrong so you can change what you have written and try again.</p> - <p>Now lets run the program.</p> + <p>Now let's run the program.</p> <pre> 4> <input>tut:double(10).</input> 20</pre> @@ -208,7 +208,7 @@ mult(X, Y) -> called variables. Variables must start with a capital letter (see the chapter <seealso marker="doc/reference_manual:expressions">"Variables"</seealso> - in the Erlang Reference Manual). Examples of variable could be + in the Erlang Reference Manual). Examples of variables could be <c>Number</c>, <c>ShoeSize</c>, <c>Age</c> etc.</p> </section> @@ -271,7 +271,7 @@ convert(N, centimeter) -> Consider:</p> <code type="none"> tut2:convert(3, inch).</code> - <p>Does this mean that 3 is in inches? or that 3 is in centimeters + <p>Does this mean that 3 is in inches? Or that 3 is in centimeters and we want to convert it to inches? So Erlang has a way to group things together to make things more understandable. We call these <em>tuples</em>. Tuples are surrounded by "{" and "}".</p> @@ -309,7 +309,7 @@ convert_length({inch, Y}) -> <p>We have shown tuples with two parts above, but tuples can have as many parts as we want and contain any valid Erlang <em>term</em>. For example, to represent the temperature of - various cities of the world we could write</p> + various cities of the world we could write:</p> <code type="none"> {moscow, {c, -10}} {cape_town, {f, 70}} @@ -325,7 +325,7 @@ convert_length({inch, Y}) -> <title>Lists</title> <p>Whereas tuples group things together, we also want to be able to represent lists of things. Lists in Erlang are surrounded by "[" - and "]". For example a list of the temperatures of various cities + and "]". For example, a list of the temperatures of various cities in the world could be:</p> <code type="none"> [{moscow, {c, -10}}, {cape_town, {f, 70}}, {stockholm, {c, -4}}, @@ -345,7 +345,7 @@ convert_length({inch, Y}) -> [2,3,4,5]</pre> <p>We use | to separate the first elements of the list from the rest of the list. (<c>First</c> has got value 1 and - <c>TheRest</c> value [2,3,4,5]).</p> + <c>TheRest</c> value [2,3,4,5].)</p> <p>Another example:</p> <pre> 20> <input>[E1, E2 | R] = [1,2,3,4,5,6,7].</input> @@ -403,7 +403,7 @@ list_length([First | Rest]) -> the remaining elements <c>Rest</c> is 1 + the length of <c>Rest</c>.</p> <p>(Advanced readers only: This is not tail recursive, there is a - better way to write this function).</p> + better way to write this function.)</p> <p>In general we can say we use tuples where we would use "records" or "structs" in other languages and we use lists when we want to represent things which have varying sizes, (i.e. where we would @@ -573,10 +573,9 @@ http://www.erlang.org/doc/r9b/doc/index.html</code> <section> <title>Writing Output to a Terminal</title> <p>It's nice to be able to do formatted output in these example, so - the next example shows a simple way to use to use - the <c>io:format</c> function. Of course, just like all other - exported functions, you can test the <c>io:format</c> function in - the shell:</p> + the next example shows a simple way to use the <c>io:format</c> + function. Of course, just like all other exported functions, you + can test the <c>io:format</c> function in the shell:</p> <pre> 31> <input>io:format("hello world~n", []).</input> hello world @@ -673,7 +672,7 @@ ok</pre> <p>Now we call <c>format_temps(Rest)</c> with the rest of the list as an argument. This way of doing things is similar to the loop constructs in other languages. (Yes, this is recursion, but don't - let that worry you). So the same <c>format_temps</c> function is + let that worry you.) So the same <c>format_temps</c> function is called again, this time <c>City</c> gets the value <c>{cape_town,{f,70}}</c> and we repeat the same procedure as before. We go on doing this until the list becomes empty, i.e. [], @@ -737,12 +736,12 @@ list_max([Head|Rest], Result_so_far) -> the next part of the function.</p> <p>Some useful operators in guards are, < less than, > greater than, == equal, >= greater or equal, =< less or - equal, /= not equal. (see the chapter - <seealso marker="doc/reference_manual:expressions">"Guard Sequences"</seealso> in the Erlang Reference Manual).</p> + equal, /= not equal. (See the chapter + <seealso marker="doc/reference_manual:expressions">"Guard Sequences"</seealso> in the Erlang Reference Manual.)</p> <p>To change the above program to one which works out the minimum value of the element in a list, all we would need to do is to write < instead of >. (But it would be wise to change - the name of the function to <c>list_min</c> :-).</p> + the name of the function to <c>list_min</c> :-).)</p> <p>Remember that I mentioned earlier that a variable could only be given a value once in its scope? In the above we see, for example, that <c>Result_so_far</c> has been given several values. This is @@ -846,7 +845,7 @@ reverse([], [3,2,1]) => write a list manipulating function it is a good idea to check that one isn't already written for you. (see <seealso marker="stdlib:lists">lists(3)</seealso>).</p> - <p>Now lets get back to the cities and temperatures, but take a more + <p>Now let's get back to the cities and temperatures, but take a more structured approach this time. First let's convert the whole list to Celsius as follows and test the function:</p> <code type="none"> @@ -890,7 +889,7 @@ format_temps(List_of_cities) -> <code type="none"> [City | convert_list_to_c(Rest)];</code> <p>We go on doing this until we get to the end of the list (i.e. - the list is empty:</p> + the list is empty):</p> <code type="none"> convert_list_to_c([]) -> [].</code> @@ -1187,11 +1186,11 @@ trunc(5.0) = 5 <pre> 74> <input>2004 rem 400.</input> 4</pre> - <p>so instead of writing</p> + <p>so instead of writing:</p> <code type="none"> trunc(Year / 400) * 400 == Year -> leap;</code> - <p>we could write</p> + <p>we could write:</p> <code type="none"> Year rem 400 == 0 -> leap;</code> @@ -1201,7 +1200,7 @@ Year rem 400 == 0 -> (see the chapter <seealso marker="doc/reference_manual:expressions">"Guard Sequences"</seealso> in the Erlang Reference Manual) (Aside for advanced readers: This is to ensure that guards don't have side - effects). Let's play with a few of these functions in the shell:</p> + effects.) Let's play with a few of these functions in the shell:</p> <pre> 75> <input>trunc(5.6).</input> 5 @@ -1268,7 +1267,7 @@ map(Fun, []) -> #Fun<erl_eval.5.123085357> 89> <input>lists:map(Add_3, [1,2,3]).</input> [4,5,6]</pre> - <p>Now lets print out the temperatures in a list of cities (yet + <p>Now let's print out the temperatures in a list of cities (yet again):</p> <pre> 90> <input>Print_City = fun({City, {X, Temp}}) -> io:format("~-15w ~w ~w~n",</input> |