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#1011
 
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Re: Principle of Orthogonal Design -
02-08-2008
, 08:41 PM
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However quantifiers in logic come with their own lexical scope. (They must, since they introduce local names.) |
integration, product, summation and limit that also introduce local
names that are invisible to the containing context, and are said to be
"bound", not "free".
I think an explicit syntax for introducing a lexical scope for a
variable that is explicitly bound to some expression works nicely.
Eg (let a=x in f(a)) is equivalent to f(x)
and the query
P(a=y, b=x) & Q(a=x, b=z))
where P,Q are relations with attributes named a,b would instead be
written as
(let a=y,b=x in P) & (let a=x, b=z in Q)
#1012
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However quantifiers in logic come with their own lexical scope. (They must, since they introduce local names.) |
integration, product, summation and limit that also introduce local
names that are invisible to the containing context, and are said to be
"bound", not "free".
I think an explicit syntax for introducing a lexical scope for a
variable that is explicitly bound to some expression works nicely.
Eg (let a=x in f(a)) is equivalent to f(x)
and the query
P(a=y, b=x) & Q(a=x, b=z))
where P,Q are relations with attributes named a,b would instead be
written as
(let a=y,b=x in P) & (let a=x, b=z in Q)
#1013
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However quantifiers in logic come with their own lexical scope. (They must, since they introduce local names.) |
integration, product, summation and limit that also introduce local
names that are invisible to the containing context, and are said to be
"bound", not "free".
I think an explicit syntax for introducing a lexical scope for a
variable that is explicitly bound to some expression works nicely.
Eg (let a=x in f(a)) is equivalent to f(x)
and the query
P(a=y, b=x) & Q(a=x, b=z))
where P,Q are relations with attributes named a,b would instead be
written as
(let a=y,b=x in P) & (let a=x, b=z in Q)
#1014
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However quantifiers in logic come with their own lexical scope. (They must, since they introduce local names.) |
integration, product, summation and limit that also introduce local
names that are invisible to the containing context, and are said to be
"bound", not "free".
I think an explicit syntax for introducing a lexical scope for a
variable that is explicitly bound to some expression works nicely.
Eg (let a=x in f(a)) is equivalent to f(x)
and the query
P(a=y, b=x) & Q(a=x, b=z))
where P,Q are relations with attributes named a,b would instead be
written as
(let a=y,b=x in P) & (let a=x, b=z in Q)
#1015
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However quantifiers in logic come with their own lexical scope. (They must, since they introduce local names.) |
integration, product, summation and limit that also introduce local
names that are invisible to the containing context, and are said to be
"bound", not "free".
I think an explicit syntax for introducing a lexical scope for a
variable that is explicitly bound to some expression works nicely.
Eg (let a=x in f(a)) is equivalent to f(x)
and the query
P(a=y, b=x) & Q(a=x, b=z))
where P,Q are relations with attributes named a,b would instead be
written as
(let a=y,b=x in P) & (let a=x, b=z in Q)
#1016
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However quantifiers in logic come with their own lexical scope. (They must, since they introduce local names.) |
integration, product, summation and limit that also introduce local
names that are invisible to the containing context, and are said to be
"bound", not "free".
I think an explicit syntax for introducing a lexical scope for a
variable that is explicitly bound to some expression works nicely.
Eg (let a=x in f(a)) is equivalent to f(x)
and the query
P(a=y, b=x) & Q(a=x, b=z))
where P,Q are relations with attributes named a,b would instead be
written as
(let a=y,b=x in P) & (let a=x, b=z in Q)
#1017
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However quantifiers in logic come with their own lexical scope. (They must, since they introduce local names.) |
integration, product, summation and limit that also introduce local
names that are invisible to the containing context, and are said to be
"bound", not "free".
I think an explicit syntax for introducing a lexical scope for a
variable that is explicitly bound to some expression works nicely.
Eg (let a=x in f(a)) is equivalent to f(x)
and the query
P(a=y, b=x) & Q(a=x, b=z))
where P,Q are relations with attributes named a,b would instead be
written as
(let a=y,b=x in P) & (let a=x, b=z in Q)
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