So why we can't change $c=1000?

As roboticus points out, you can make that change. That is, you can overwrite the value in $c -- currently the address of the constant 99 -- with any other value.

What you cannot do is overwrite the value held at the address held in $c, because it is a constant.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

RIP Neil Armstrong

In reply to Re^3: Modification of a read-only value attempted by BrowserUk
in thread Modification of a read-only value attempted by panku

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