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sridhar n
sridhar n

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Python Day 7 – The / and * in Function Definitions

#python #career #function #arguments

First, positional vs keyword arguments

Positional arguments are matched by their position (order).

def intro(name, age):
    print(name, "is", age, "years old")

intro("Sridhar", 26)   # Sridhar is 26 years old
intro(26, "Sridhar")   # 26 is Sridhar years old
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The first value goes to name and the second goes to age. Swap the order and you get the wrong result.

Keyword arguments are matched by their name, so the order doesn't matter.

intro(name="Sridhar", age=26)   # Sridhar is 26 years old
intro(age=26, name="Sridhar")   # Sridhar is 26 years old
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You can mix the two, but positional ones must come first:

intro("Sridhar", age=26)    # works
intro(name="Sridhar", 26)   # SyntaxError: positional argument follows keyword argument
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Normally Python lets you pass an argument either way. The / and * symbols let you force one style.

/ → positional-only arguments 

def calculate(a, b, /):
    print(a + b)

calculate(10, 20)        # works, prints 30
calculate(a=10, b=20)    # TypeError
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Anything before / has to be passed by position. You can't use the name.

* → keyword-only arguments 

def calculate(a, *, b):
    print(a + b)

calculate(a=10, b=20)    # works
calculate(10, b=20)      # works
calculate(10, 20)        # TypeError
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Anything after * has to be passed by name.

Quick way to remember it:

  • / → "everything before me is positional only"
  • * → "everything after me is keyword only"

Functions can return things 

def play():
    teamA = 300
    teamB = 290
    if teamA > teamB:
        return "Winner Trophy"
    else:
        return "Runner Trophy"

hand = play()
print(hand)   # Winner Trophy
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return hands a value back to whoever called the function.

The career part

What I took away from it:

  • AI tools (Claude, Copilot, etc.) are making some jobs easier, but companies still want people who understand code, not just people who can generate it.
  • Interviews still test flow charts, pseudocode and algorithms. Logic matters more than syntax.
  • Build proof of your interest. Write blogs (that's why I'm on dev.to), go to tech meetups, talk to technical people.
  • Learn the fundamentals properly (Python, Java, databases). That's what lasts.

So here I am, blogging.

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