question 187 Files & Directories · medium

Combine the daily exports

A folder holds one CSV export per day, each starting with the same header line. Finance wants a single file. Write a function that combines them, keeping the header once.

Functioncombine_exports(folder, dest)

Readsevery *.csv file in folder, in sorted name order (other files are ignored)

Writesdest: the first file's header line once, then every data line of every file, each ending with \n; blank lines are dropped; dest is replaced if it exists

Returnsthe number of data lines written

Edge casesa file may hold only its header, and a file's last line may have no newline; with no CSV files at all, dest is created empty and the result is 0

Examples

callcombine_exports('daily', 'all.csv')returns4