Erlang 实现~p和~w格式与io_lib:format的混合

假设我有一个任意格式的字符串和som对应的数据，数据包含带有字符串元素的元组。作为一个（缩短的）示例：

出于特定目的，我希望打印相同的输出，但只打印一行。我希望实现与“~p”相同的格式设置（即，

数据

应打印为

{“ABC”}

而不是

{[65,66,67]}

。这可能吗

我想我可以分三步来做：

• io_lib:format

  with

  ~p

• 循环遍历结果字符串并删除所有新行字符
• 正则表达式将多个连续空间的所有序列替换为单个空间

---

但是这种方法似乎冗长且效率低下。有没有更好的方法来使用OTP函数来实现这一点？

如果您知道输出的宽度永远不会超过（比如）一百万个字符，则可以指定

~p

说明符的输出宽度：

io:format("~1000000p", [Data]).

---

正如Legosca所指出的，

io:format/2

试图在漂亮的打印元素和行长度等方面保持礼貌，您可以通过格式字符串参数对每个元素进行调整。请注意，这意味着如果使用格式控制序列，格式本身就是控制每个元素输出长度的地方

允许您声明行的总长度（相对于每个元素）的另一种方法是。我倾向于发现此特定函数对于日志消息格式设置更有用：

1> T = {"Some really long things","are in this tuple","but it won't really matter","because they will be in line"}.
{"Some really long things","are in this tuple",
 "but it won't really matter","because they will be in line"}
2> io:format("~tp~n", [T]).
{"Some really long things","are in this tuple","but it won't really matter",
 "because they will be in line"}
3> S = io_lib:print(T, 1, 1000, -1).
[123,
 ["\"Some really long things\"",44,"\"are in this tuple\"",
  44,"\"but it won't really matter\"",44,
  "\"because they will be in line\""],
 125]
4> lists:flatten(S).
"{\"Some really long things\",\"are in this tuple\",\"but it won't really matter\",\"because they will be in line\"}"
5> io:format("~ts~n", [S]).
{"Some really long things","are in this tuple","but it won't really matter","because they will be in line"}
ok

仔细阅读文档，了解更多信息。实际上，文档中包含了很多不时弹出的功能

请记住，如果目标是控制终端本身，您还可以通过打印单个字符和使用ASCII控制序列来完成大量有趣的工作。如果您要解决的问题是构建基于文本的接口或som，则使用逐字符或逐blit屏幕更新字符串输出是一个强大的工具这是相似的

1> T = {"Some really long things","are in this tuple","but it won't really matter","because they will be in line"}.
{"Some really long things","are in this tuple",
 "but it won't really matter","because they will be in line"}
2> io:format("~tp~n", [T]).
{"Some really long things","are in this tuple","but it won't really matter",
 "because they will be in line"}
3> S = io_lib:print(T, 1, 1000, -1).
[123,
 ["\"Some really long things\"",44,"\"are in this tuple\"",
  44,"\"but it won't really matter\"",44,
  "\"because they will be in line\""],
 125]
4> lists:flatten(S).
"{\"Some really long things\",\"are in this tuple\",\"but it won't really matter\",\"because they will be in line\"}"
5> io:format("~ts~n", [S]).
{"Some really long things","are in this tuple","but it won't really matter","because they will be in line"}
ok