Shopping cart total

# Self-authored for the EML case corpus (no external origin). A shopping
# cart as a list of `(item_name, unit_price, quantity)` tuples; computes
# each line-item subtotal and the grand total via a loop with tuple
# subscript access, then prints an itemized receipt using `%`-string
# formatting. `"%.2f" % (x,)` was tried first and works under real Python,
# but the interpreter's own `%`-formatter throws `ValueError: unsupported
# format character '.'` (precision specs aren't modeled) — so amounts are
# rounded to the nearest cent by hand (`int(x * 100 + 0.5)`) and rendered as
# a zero-padded "dollars.cents" string via `%s`/`%d`, wrapped in a small
# `format_money` helper to avoid repeating that logic per line.

cart^+[("Coffee Beans (12oz)", 8.99, 2), ("Almond Milk", 3.49, 3),
       ("Granola Bars (6-pack)", 4.25, 1), ("Bananas (lb)", 0.50, 6)]

def format_money(amount):
    int(amount * 100 + 0.5) => cents_total
    int(cents_total / 100) => dollars
    (cents_total % 100) => cents_rem
    if cents_rem < 10:
        "0" + str(cents_rem) => cents_str
    else:
        str(cents_rem) => cents_str
    return str(dollars) + "." + cents_str

grand_total^+0
"Receipt:"^0
for entry in cart:
    entry[0] => name
    entry[1] => unit_price
    entry[2] => qty
    (unit_price * qty) => subtotal
    grand_total^+subtotal
    format_money(subtotal) => price_str
    ("%s x%d = $%s" % (name, qty, price_str)) => line
    line^0

format_money(grand_total) => total_str
("Grand total: 

      
      

        

          
EML
          
Starting…
        
      
    
  quot; + total_str) => grand_line
grand_line^0

cart = [("Coffee Beans (12oz)", 8.99, 2), ("Almond Milk", 3.49, 3), ("Granola Bars (6-pack)", 4.25, 1), ("Bananas (lb)", 0.50, 6)]

def format_money(amount):
    cents_total = int(amount * 100 + 0.5)
    dollars = int(cents_total / 100)
    cents_rem = cents_total % 100
    if cents_rem < 10:
        cents_str = "0" + str(cents_rem)
    else:
        cents_str = str(cents_rem)
    return str(dollars) + "." + cents_str

grand_total = 0
print("Receipt:")
for entry in cart:
    name = entry[0]
    unit_price = entry[1]
    qty = entry[2]
    subtotal = unit_price * qty
    grand_total += subtotal
    price_str = format_money(subtotal)
    line = "%s x%d = $%s" % (name, qty, price_str)
    print(line)
total_str = format_money(grand_total)
grand_line = "Grand total: 

      
      

        

          
EML
          
Starting…
        
      
    
  quot; + total_str
print(grand_line)

Receipt:
Coffee Beans (12oz) x2 = $17.98
Almond Milk x3 = $10.47
Granola Bars (6-pack) x1 = $4.25
Bananas (lb) x6 = $3.00
Grand total: $35.70

Trace event types