while(arraySize--) array.push(value);
no initialization (that i know of)
Update
Since ever posting this answer 4 years ago, people seem to keep coming back here for this answer. For benchmarking purposes I made a JSPerf with some different solutions.
The solution above here isn’t the quickest, although it’s short. To stick to the same short style, but with a better performance:
while(size--) array[size] = value;
Update Feb 2016 Updated the JSPerf with a new revision with more testcases.
If performance doesn’t matter and you want a one-liner:
var value = 1234, // can be replaced by a fixed value size = 1000, // can be replaced by a fixed value array = Array.apply(null,{length: size}).map(function() { return value; });
A more performant solution (in one, dirty, line): Be aware: this replaces existsing value, size and i variables in the scope
for(var i = 0, value = 1234, size = 1000, array = new Array(1000); i < size; i++) a