Why does checking a variable against multiple values with OR only check the first value

Question

I want to check if a variable has one of multiple values   I m confused about why or doesn t work in this situation   I was following a tutorial that gave the example if  a or b    but when I try to do this it only checks the variable against the first value   What is wrong with my check   name   raw input  Please type in your name     if len name   lt  5      print  Your name has fewer than 5 characters  elif len name     5      print  Your name has exactly 5 characters      if name      Jesse  or  jesse            print  Hey Jesse   else      print  Your name has greater than 5 characters

User · Answer

if name in   Jesse    jesse      would be the correct way to do it   Although  if you want to use or  the statement would be  if name     Jesse  or name     jesse        gt  gt  gt    Jesse  or  jesse    Jesse    evaluates to  Jesse   so you re essentially not testing for  jesse  when you do if name      Jesse  or  jesse    since it only tests for equality to  Jesse  and does not test for  jesse   as you observed

User · Answer

Jesse  or  jesse     The above expression tests whether or not  Jesse  evaluates to True  If it does  then the expression will return it  otherwise  it will return  jesse    The expression is equivalent to writing    Jesse  if  Jesse  else  jesse    Because  Jesse  is a non-empty string though  it will always evaluate to True and thus be returned    gt  gt  gt  bool  Jesse      Non-empty strings evaluate to True in Python True  gt  gt  gt  bool        Empty strings evaluate to False False  gt  gt  gt   gt  gt  gt    Jesse  or  jesse    Jesse   gt  gt  gt      or  jesse    jesse   gt  gt  gt    This means that the expression   name      Jesse  or  jesse     is basically equivalent to writing this   name     Jesse      In order to fix your problem  you can use the in operator     Test whether the value of name can be found in the tuple   Jesse    jesse   if name in   Jesse    jesse      Or  you can lowercase the value of name with str lower and then compare it to  jesse  directly     This will also handle inputs such as  JeSSe    jESSE    JESSE   etc  if name lower       jesse

User · Answer

The or operator returns the first operand if it is true  otherwise the second operand   So in your case your test is equivalent to if name     Jesse    The correct application of or would be   if  name     Jesse   or  name     jesse

User · Answer

If you want case-insensitive comparison  use lower or upper   if name lower       jesse

[python] Why does checking a variable against multiple values with `OR` only check the first value?

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