如何修改Clojure代码实现指定格式的文件内容输出？

Let's break down how to modify your code to get the exact output you want:

Key Changes Needed #

Your current code uses the 0-based line index as the "ID", but you need to either:

• Use the original ID from each line (and sort by it), or
• Assign a new sequential ID starting at 1 (ignoring the original line ID)

Based on your desired output example, it looks like you want to use the original ID from each line. Here's how to do that:

Modified Code for Data Structure (Sorted by Original ID) #

(->> (line-seq (clojure.java.io/reader "test.txt"))
     (map #(vec (.split % #"\|")))  ; Split each line into [ID, Name, Country, Phone]
     (map (fn [parts]
            [(Integer/parseInt (first parts))  ; Convert string ID to integer
             (vec (rest parts))]))  ; Keep everything except the original ID
     (sort-by first))  ; Sort entries by the ID

This will produce a sorted sequence like:

([1 ["Austin" "Germany" "34-554567"]] [2 ["Mary Jane" "Australia" "45-78647"]] [3 ["King Kong" "New-Zealand" "35-467533"]])

If You Want the Exact String Format #

To get the output as a string matching your desired example:

(clojure.string/join " "
                     (map (fn [[id vals]]
                            (str id ":[" (clojure.string/join " " (map #(str "\"" % "\"") vals)) "]"))
                          (->> (line-seq (clojure.java.io/reader "test.txt"))
                               (map #(vec (.split % #"\|")))
                               (map (fn [parts] [(Integer/parseInt (first parts)) (vec (rest parts))]))
                               (sort-by first))))

This will output:

1:["Austin" "Germany" "34-554567"] 2:["Mary Jane" "Australia" "45-78647"] 3:["King Kong" "New-Zealand" "35-467533"]

Alternative: Sequential IDs Starting at 1 (Ignore Original ID) #

If you want to ignore the original line IDs and assign a new sequential ID starting at 1:

(->> (line-seq (clojure.java.io/reader "test.txt"))
     (map #(vec (.split % #"\|")))
     (map #(vec (rest %)))  ; Drop original ID from data
     (map-indexed (fn [idx vals] [(inc idx) vals]))  ; Assign 1-based sequential ID
     (sort-by first))  ; Sort by the new ID (which matches line order)

Explanation of Changes #

1. Replace Index with Original ID: Instead of using map-indexed for IDs, we extract the first element of each split line and convert it to an integer (so sorting works correctly).
2. Trim Unwanted Data: We use (rest parts) to keep only the name, country, and phone number.
3. Sort: sort-by first ensures the entries are ordered by ID as requested.
4. String Formatting: For the exact string output, we use clojure.string/join and str to format each entry into the desired ID:[...] structure.

内容的提问来源于stack exchange，提问作者Prishu