blocks|key|1317090|text|我不知道是否可以更改shell的默认行为，但您至少可以使用io:format正确地格式化输出。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1317091|下面是一个示例：|1317092|1>+io:format("~p~n",+[[65,+66,+67]]).
"ABC"
ok
2>+io:format("~w~n",+[[65,+66,+67]]).
[65,66,67]
ok|code-block|syntax|javascript|1317093|由于shell仅用于实验/维护，因此io:format()至少应该足以满足您的实际应用程序。也许你也应该考虑编写自己的格式/打印方法，例如formatPerson()或类似的东西，它可以很好地格式化所有东西。|style|CODE|1317094|entityMap|0|LINK|mutability|MUTABLE|url|http://erlang.org/doc/man/io.html^0|T|9|0|0|0|0|I|B|1X|E|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@$A|X|B|Y|1|Z]]|C|$]]|$1|D|3|E|5|6|7|10|8|@]|9|@]|C|$]]|$1|F|3|G|5|H|7|11|8|@]|9|@]|C|$I|J]]|$1|K|3|L|5|6|7|12|8|@$A|13|B|14|M|N]|$A|15|B|16|M|N]]|9|@]|C|$]]|$1|O|3|-4|5|6|7|17|8|@]|9|@]|C|$]]]|P|$Q|$5|R|S|T|C|$U|V]]]]

I don't know if it's possible to change the default behavior of the shell, but you can at least format your output correctly, using <a href="http://erlang.org/doc/man/io.html" rel="nofollow noreferrer">io:format</a>.

Here is an example:

<pre><code>1&gt; io:format("~p~n", [[65, 66, 67]]).
"ABC"
ok
2&gt; io:format("~w~n", [[65, 66, 67]]).
[65,66,67]
ok
</code></pre>

And since the shell is only for experimenting / maintenance, <code>io:format()</code> should be at least enough for your real application. Maybe you should also consider to write your own format/print method, e.g. <code>formatPerson()</code> or something like that, which formats everything nicely.

blocks|key|1102204|text|问题是字符串不是Erlang中的类型。字符串只是一个整数列表，因此shell无法区分可打印字符串和泛型列表。不知道这个答案是否能回答你的问题。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1102205|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

The problem is that the string is not a type in Erlang. A string is just a list of integers, so there's no way for the shell to distinguish a printable string from a generic list. Don't know if this answer to your question.

blocks|key|1317228|text|我倾向于通过在shell中的列表中添加一个原子来完成此操作。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1317229|例如：|1317230|Eshell+V5.7.4++(abort+with+%5EG)
1>+[65,66,67].
"ABC"
2>+[a%7C[65,66,67]].
[a,65,66,67]|code-block|syntax|javascript|1317231|当然也可以是a,65,66,67。但是a%7Cfun_that_returns_a_list()会在大多数时候打印“正确的东西”。|1317232|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|N|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|O|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|P|8|@]|9|@]|A|$]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

I tend to do it by prepending an atom to my list in the shell.

for example:

<pre><code>Eshell V5.7.4 (abort with ^G)
1&gt; [65,66,67].
"ABC"
2&gt; [a|[65,66,67]].
[a,65,66,67]
</code></pre>

could also be [a,65,66,67], of course. but [a|fun_that_returns_a_list()] will print "the right thing(ish) most of the time"

blocks|key|1317301|text|不，没有办法禁用它。我发现的最好的替代方法是在查询中显式地打印出值(使用io:format)，或者在do：io:format("~w\n",+[v(-1)])之后输出。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1317302|entityMap^0|10|9|1H|Q|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]|$9|K|A|L|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|M|8|@]|D|@]|E|$]]]|G|$]]

No, there is no way to disable it. The best alternative I find is to either explicitly print out the value in the query (with <code>io:format</code>) or after the fact do: <code>io:format("~w\n", [v(-1)])</code>.

blocks|key|1102398|text|我不认为你能阻止它。给一个原子加上前缀看起来很麻烦--它确实改变了你原来的字符串。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1102399|我通常使用list:flatten(+string+)将其强制为字符串-特别是io_lib:format()的返回值并不总是打印为字符串。在其上使用list:flatten()使其成为一个。|1102400|我使用下面的“C风格”：|1102401|sprintf(Format)+->
+++++sprintf(Format,+[]).
sprintf(Format,+Args)+->
++++lists:flatten(io_lib:format(Format,+Args)).|code-block|syntax|javascript|1102402|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|N|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|O|8|@]|9|@]|A|$]]|$1|F|3|G|5|H|7|P|8|@]|9|@]|A|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

I don't think you can prevent it. 
Prepending an atom seems like a kludge - it does alter your original string.

I typically use lists:flatten(String) to force it to a string - especially the returnvalue of io_lib:format() does not always print as a string. Using lists:flatten() on it makes it one.

I use the following "C-style":

<pre><code>sprintf(Format) -&gt;
 sprintf(Format, []).
sprintf(Format, Args) -&gt;
 lists:flatten(io_lib:format(Format, Args)).
</code></pre>

blocks|key|1102436|text|As+of+Erlang/OTP+R16B，您可以使用函数shell:strings/1来打开或关闭此功能。请注意，它还会影响实际应为字符串的内容的打印，如以下示例中的"foo"：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1102437|1>+{[8,9,10],+"foo"}.
{"\b\t\n","foo"}
2>+shell:strings(false).
true
3>+{[8,9,10],+"foo"}.+++
{[8,9,10],[102,111,111]}|code-block|syntax|javascript|1102438|entityMap|0|LINK|mutability|MUTABLE|url|http://www.erlang.org/download/otp_src_R16B.readme|1|http://www.erlang.org/doc/man/shell.html#strings-1^0|2C|5|0|L|0|T|F|1|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@$9|V|A|W|B|C]]|D|@$9|X|A|Y|1|Z]|$9|10|A|11|1|12]]|E|$]]|$1|F|3|G|5|H|7|13|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|14|8|@]|D|@]|E|$]]]|L|$M|$5|N|O|P|E|$Q|R]]|S|$5|N|O|P|E|$Q|T]]]]

<a href="http://www.erlang.org/download/otp_src_R16B.readme">As of Erlang/OTP R16B</a>, you can use the function <a href="http://www.erlang.org/doc/man/shell.html#strings-1">shell:strings/1</a> to turn this on or off. Note that it also affects printing of things that are actually meant to be strings, such as <code>"foo"</code> in the following example:

<pre><code>1&gt; {[8,9,10], "foo"}.
{"\b\t\n","foo"}
2&gt; shell:strings(false).
true
3&gt; {[8,9,10], "foo"}. 
{[8,9,10],[102,111,111]}
</code></pre>

blocks|key|1317423|text|您可以从Erlang+R16B开始使用shell:strings/1+function禁用这种行为。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1317424|只需记住，这是所有节点shell的全局选项，在较长存活的节点中播放完shell后，将其设置为全局选项可能是明智的。|1317425|entityMap|0|LINK|mutability|MUTABLE|url|http://www.erlang.org/doc/man/shell.html#strings-1^0|J|F|J|O|0|0|0^^$0|@$1|2|3|4|5|6|7|P|8|@$9|Q|A|R|B|C]]|D|@$9|S|A|T|1|U]]|E|$]]|$1|F|3|G|5|6|7|V|8|@]|D|@]|E|$]]|$1|H|3|-4|5|6|7|W|8|@]|D|@]|E|$]]]|I|$J|$5|K|L|M|E|$N|O]]]]

You can disable such behavior with <a href="http://www.erlang.org/doc/man/shell.html#strings-1"><code>shell:strings/1</code> function</a> starting with Erlang R16B.

Just remember that this is option global to all node shells, and it might be wise to set it back after finishing playing is shell in longer living nodes.

<a href="http://en.wikibooks.org/wiki/Erlang_Programming/Terms#Strings" rel="noreferrer">The Erlang shell "guesses" whether a given list is a printable string and prints it that way for convenience.</a> Can this "convenience" be disabled?

问我可以在Erlang shell中禁止将小整数列表打印为字符串吗？
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问我可以在Erlang shell中禁止将小整数列表打印为字符串吗？
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