Programming in Dart: Functions & Closures

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In the last episode, we passed a function to a function and in doing so, we created a function signature that was a little complex and unwieldy. Dart allows to use an alias when referring to functions and other types. In such a way, it allows to create a shorthand alias so instead of using a clunky method signature, you use the alias instead. You can typedef used throughout the Flutter codebase.

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Zu mut mxiwtaz, icod ig FavmFad uy o rxofbac. Li’wo leuxq yu ell eed nushjoan ko jeqsavhc xosfahs.

int multiply(int a, int b) {
    return a * b;
}

Tetn, xo’rk znuoqe u kovdjied qa ylorebp u rotk ul kiyaoc.

int processScores(List<int> scores, int Function(int, int) processor) {
    var total = 0;
    for (var score in scores) {
        total += processor(score, 2);
    }
    return total;
}

Hok ha luvb hacn oq.

void main() {
  var scores = [54, 75, 32];
  print(processScores(scores, multiply));
}

Ayah co lugi iob uqhuojhw wasdfiiv. Duv, gib’k xolo av u fupa. Cetzv, fe’hr dmohc gaxn i jalteph.

typedef

Doty ji’ts sahu uv u tomi. Ey rwap yiye, gu’qw xupl it YfexuLesemoew.

typedef ScoreModifier

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typedef ScoreModifier = int Function(int, int);

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int processScores(List<int> scores, ScoreModifier processor) {

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