in reply to Equality operators

As '==' is the numeric equality operator, it doesn't make sense to use it for strings. For all Strings you should use eq instead of ==, ne instead of != and cmp instead of <=>.

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Re^2: Equality operators
by jkva (Chaplain) on Apr 25, 2006 at 11:41 UTC
    Mantadin, thank you. I am aware of this, however I am wondering why '1' == '1foo' evals to true while '1' eq 'foo1' does not.
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      When converting strings to numbers, Perl only looks at the start of the string. '1foo' becomes 1 and 'foo1' becomes 0.

      --
      <http://dave.org.uk>

      "The first rule of Perl club is you do not talk about Perl club."
      -- Chip Salzenberg

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      because strings are automatically converted to numbers when needed. '1foo' is converted to 1 and 'foo1' is converted to 0.
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      Others have already explained how the conversion works, but if you want to see for yourself the number into which a string is coerced, add 0 to the string. 

      print(0+'a',    "\n");  # 0
print(0+'b',    "\n");  # 0
print(0+'1',    "\n");  # 1
print(0+'2',    "\n");  # 2
print(0+'1foo', "\n");  # 1
print(0+'foo1', "\n");  # 0

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