Putting It All Together

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// Tutorial 20: Putting It All Together
// A mini project: word frequency counter

func buildFreqMap(text) {
    // Count word frequencies using env as a map
    let env = ""
    let word = ""
    let i = 0
    while i < len(text) {
        let ch = text[i]
        if ch == " " || ch == "\n" || ch == "\t" {
            if len(word) > 0 {
                let prev = envGet(env, word)
                if len(prev) == 0 {
                    env = envSet(env, word, "1")
                } else {
                    env = envSet(env, word, "" + (toInt(prev) + 1))
                }
                word = ""
            }
        } else {
            word = word + ch
        }
        i = i + 1
    }
    // Handle last word
    if len(word) > 0 {
        let prev = envGet(env, word)
        if len(prev) == 0 {
            env = envSet(env, word, "1")
        } else {
            env = envSet(env, word, "" + (toInt(prev) + 1))
        }
    }
    emit env
}

just run {
    let text = "the cat sat on the mat the cat ate the rat"
    kp("Text: " + text)
    kp("")

    let freq = buildFreqMap(text)

    // Check specific words
    let words = "the,cat,sat,on,mat,ate,rat"
    let i = 0
    let n = count(words)
    while i < n {
        let w = split(words, i)
        let c = envGet(freq, w)
        if len(c) > 0 {
            kp("  '" + w + "' appears " + c + " time(s)")
        }
        i = i + 1
    }

    kp("")
    kp("Tutorial complete! You now know the key features of Krypton.")
}

Click ▶ Run to execute. Lessons using k:fs/k:http/match/struct need the real runtime.

Tip: this code box is editable — tweak it, then hit Run, or copy into a .k file and run locally.

Run it locally: kcc -r tutorial/20_putting_it_together.k

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