Cumulated sum of the elements of a list : cumSum

cumSum takes as argument a list l (resp sequence) of numbers or of strings.
cumSum returns the list (resp sequence) with same length as l and with k-th element the sum (or concatenation) of the elements $\tt l[0],..,l[k]$.
Input :

cumSum(sqrt(2),3,4,5,6)

Output :

sqrt(2),3+sqrt(2),3+sqrt(2)+4,3+sqrt(2)+4+5,

3+sqrt(2)+4+5+6

Input :

normal(cumSum(sqrt(2),3,4,5,6))

Output :

sqrt(2),sqrt(2)+3,sqrt(2)+7,sqrt(2)+12,sqrt(2)+18

Input :

cumSum(1.2,3,4.5,6)

Output :

1.2,4.2,8.7,14.7

Input :

cumSum([0,1,2,3,4])

Output :

[0,1,3,6,10]

Input :

cumSum("a","b","c","d")

Output :

"a","ab","abc","abcd"

Input :

cumSum("a","ab","abc","abcd")

Output :

"a","aab","aababc","aababcabcd"