grails - 如何将 map 动态添加到列表？

Question

如我在问题中所述，我想将 map 动态添加到列表中，并避免使用相同的键添加 map ，我正在尝试这样做

def myList = []
["a", "b", "c", "c", "d", "e", "f", "a" ,"f"].each { letter ->
   def map = [:]

   //here I want to check if current letter exist as key in myList
   //if it is true then avoid next code

   map.put(letter, [])
   myList << map
}

println myList

在现实生活中，字母将由用户添加。

Answer 1

干得好:

def myList = []

["a", "b", "c", "c", "d", "e", "f", "a" ,"f"].each { letter ->  
   if(!myList.find { it.keySet().contains(letter) })
      myList << [(letter): []]
}
assert myList ==  [[a:[]], [b:[]], [c:[]], [d:[]], [e:[]], [f:[]]]

或者您可以简单地:

def myList = ["a", "b", "c", "c", "d", "e", "f", "a" ,"f"].unique().collect { [(it):[]] }
assert myList ==  [[a:[]], [b:[]], [c:[]], [d:[]], [e:[]], [f:[]]]