[Web4lib] global variables versus local variables

John Fitzgibbon jfitzgibbon at Galwaylibrary.ie
Mon May 23 04:46:34 EDT 2005


When programming and when writing scripts, we are encouraged to use
variables that are local in scope whenever we can.

However, defining a variable within a sub-routine, as in VbScript, means
the variable is defined every time the sub-routine is run whereas
defining it outside the sub-routine means the variable is defined only
once. Why is it more efficient to define a variable within a

Also, defining a variable within a loop causes the variable to be
defined afresh with each instance of the loop. Again this appears
inefficient but is generally done when a 'for loop' is run in

I don't doubt that local variables have their uses; I'm simply seeking
an explanation.


John Fitzgibbon

John Fitzgibbon

Galway Public Library
Island House
Cathedral Square

p: 00 353 91 562471
f: 00 353 91 565039
w: http://www.galwaylibrary.ie 

Tá eolas atá príobháideach agus rúnda sa ríomhphost seo 
agus aon iatán a ghabhann leis agus is leis an duine/na daoine
sin amháin a bhfuil siad seolta chucu a bhaineann siad. 
Mura seolaí thú, níl tú údaraithe an ríomhphost nó aon iatán 
a ghabhann leis a léamh, a chóipáil ná a úsáid. 
Má tá an ríomhphost seo faighte agat trí dhearmad, 
cuir an seoltóir ar an eolas thrí aischur ríomhphoist 
agus scrios ansin é le do thoil. 

This e-mail and any attachment contains information which is 
private and confidential and is intended for the addressee 
only. If you are not an addressee, you are not authorised 
to read, copy or use the e-mail or any attachment. 
If you have received this e-mail in error, please notify 
the sender by return e-mail and then destroy it. 

More information about the Web4lib mailing list