scripting.asc

// Using Ascend for scripts: running programs, files and folders, CSV,
// hashing and dates.

// Run a command through the shell and capture what it prints.
result := run("echo hello from the shell")
print("exit code", result.code, "printed:", trim(result.stdout))

// Work in a scratch folder inside the system's temporary folder.
folder := path_join(temp_dir(), "ascend-scripting-" + uuid()[0:8])
make_dir(folder)

try {
    // Write a CSV file, then read it back and summarize it.
    csv_file := path_join(folder, "prices.csv")
    write_file(csv_file, csv_stringify([["item", "price"], ["tea", 2.5], ["cake", 4], ["coffee", 3.25]]))

    table := csv_parse(read_file(csv_file))
    map<string, f64> prices = {row[0]: f64(row[1]) for row in table[1:]}
    printf("%d items, %.2f in total, the most expensive is %s\n", len(prices), sum(values(prices)),
           max_by(keys(prices), item => prices[item]))

    // More files in a subfolder, then a look at everything.
    make_dir(path_join(folder, "notes"))
    write_file(path_join(folder, "notes", "todo.txt"), "buy milk\nwrite more Ascend\n")
    for (string file : walk_dir(folder)) {
        path := path_join(folder, file)
        printf("%-16s %3d bytes  sha256 %s...\n", file, file_size(path), sha256(read_file(path))[0:12])
    }
} finally {
    remove_dir(folder)  // clean up, even if something above failed
}

print("the scratch folder is gone:", !is_dir(folder))

today := now()
printf("today is %04d-%02d-%02d, day %d of the year\n", today.year, today.month, today.day, today.yearday)