53 lines
1.1 KiB
Go
53 lines
1.1 KiB
Go
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// For more tutorials: https://blog.learngoprogramming.com
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//
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// Copyright © 2018 Inanc Gumus
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// Learn Go Programming Course
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// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
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//
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package main
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import (
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"fmt"
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"math"
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"os"
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"strconv"
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)
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// This program contains a lot of comments
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// Non-commented version is in /without-comments/main.go
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func main() {
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// You cannot use this syntax.
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//
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// feetInMeters is declared
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// when the declaration completes,
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// (at the end of the whole declaration)
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//
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// And, it's not easy to read
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//
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// const feetInMeters, feetInYards float64 = 0.3048,
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// feetInMeters / 0.9144
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const (
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feetInMeters = 0.3048
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feetInYards = feetInMeters / 0.9144
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// cannot call runtime funcs
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// feetInYards = math.Round(feetInYards)
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)
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// Immutable: You cannot assign new values
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// feetInYards = 0.333333
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arg := os.Args[1]
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feet, _ := strconv.ParseFloat(arg, 64)
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meters := feet * feetInMeters
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yards := math.Round(feet * feetInYards)
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fmt.Printf("%g feet is %g meters.\n", feet, meters)
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fmt.Printf("%g feet is %g yards.\n", feet, yards)
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}
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