Golang : How to check if input from os.Args is integer?
While coding out the Ackermann codes, I need to check if the input parameters are in numeric and not some alphabet characters.
Golang's os.Args[]
function will return the result as string type and I need to check if the input parameters are indeed numeric and not alphabet.
To do that, use the strconv.ParseInt()
function to convert the parameters to integer and if it failed, prompt error and abort further execution.
// convert input (type string) to integer
first, err := strconv.ParseInt(os.Args[1], 10, 0)
if err != nil {
fmt.Println("First input parameter must be integer")
os.Exit(1)
}
second, err := strconv.ParseInt(os.Args[2], 10, 0)
if err != nil {
fmt.Println("Second input parameter must be integer")
os.Exit(1)
}
Example test results :
./ackermnn 3 abc
Second input parameter must be integer
./ackermnn a2b 2
First input parameter must be integer
Full example at https://www.socketloop.com/tutorials/golang-ackermann-function-example Reference :
https://www.socketloop.com/tutorials/golang-ackermann-function-example
See also : Golang : Ackermann function example
By Adam Ng
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