Scala - 以功能方式修改字符串 [英] Scala - string modification in a functional manner

问题描述

只是想知道是否有更实用的方法来实现某些功能如下所示：

  def expand（exp：String）：String = {
 var result = exp $ b $ （b）为（（k，v）<  -  libMap）{result = result.replace（k，（％s）.format（v））} 
结果
} 
  

或者一般而言，给定一个字符串和一些可迭代集合，遍历集合并为每个元素增量修改输入字符串。

干杯

解决方案

  var result = init 
 for（foo<  -  bar）{result = f（result，foo）} 
结果
  

可以在功能上表示为

  bar.foldLeft（init）（f）
  

case this becomas：

  l ibMap.foldLeft（exp）{case（result，（k，v））=> result.replace（k，（％s）。format（v））} 
  

I'm just starting Scala and so getting my head around doing things in a more functional style.

Just wondering if there is a more functional way to achieve something like the following:

def expand(exp: String): String = {
  var result = exp
  for ((k,v) <- libMap) {result = result.replace(k, "(%s)".format(v))}
  result
}

Or in general terms, given a string and some iterable collection, go through the collection and for every element, incrementally modify the input string.

Cheers

解决方案

Generally the pattern

var result = init
for (foo <- bar) { result = f(result, foo)}
result

can be expressed functionally as

bar.foldLeft(init)(f)

So for your case this becomas:

libMap.foldLeft(exp){ case(result, (k,v)) => result.replace(k, "(%s)".format(v))}

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