How Can I Check if a String Represents an Integer Without Using Try/Except?

Verifying Integer Representation of a String Without Try/Except

In programming, it's often necessary to determine whether a string represents an integer value. Typically, this is achieved using a try/except block, but there are alternative methods that avoid this mechanism.

Using isdigit()

For positive integers, you can leverage the isdigit() method:

"16".isdigit()  # Returns True

However, this approach fails for negative integers.

Combining String Analysis

A more comprehensive solution involves analyzing the string's characters:

def check_int(s):
    if s[0] in ('-', '+'):  # Handle negative or positive sign
        return s[1:].isdigit()  # Verify if the remaining string is digits
    return s.isdigit()  # Positive integers

This function considers the presence of a leading sign and verifies the rest of the string for digits.

Example Usage

check_int("3.14") == False
check_int("-7")   == True

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