Factorial in Whitespace
This example uses a slightly different method of commenting — each command is preceded with its literal description. Numbers and labels are enclosed in brackets.
The example works as follows: heap is used to store variables (1 — index of the first factorial which doesn’t need to be calculated, 2..5 — ASCII-codes of special characters used in printing, 6 and 7 — current number and its factorial), and stack is used to run commands). Factorial is calculated iteratively, on each iteration previously calculated values are printed, and new ones are calculated and stored to memory. After this, the newly calculated number is compared with contents of cell 1: if it is less, the loop continues, otherwise it halts.
A curious thing to note is that in Whitespace numeric system zero is “negative”: a number must have at least one Tab in its notation, and binary notation of zero has no 1s, so it has to be written as Tab (only sign bit).
push_1 { }
push_17 { }
store push_2 { }
push_33 { }
store push_3 { }
push_32 { }
store push_4 { }
push_61 { }
store push_5 { }
push_10 { }
store push_6 { }
push_0 { }
store push_7 { }
push_1 { }
store label
{ }
printing_block_push_6 { }
retrieve print_as_number
push_2 { }
retrieve print_as_char
push_3 { }
retrieve print_as_char
push_4 { }
retrieve print_as_char
push_3 { }
retrieve print_as_char
push_7 { }
retrieve print_as_number
push_5 { }
retrieve print_as_char
increase_counter_block_push_6 { }
push_6 { }
retrieve push_1 { }
add store calculate_next_factorial_block_push_7 { }
push_7 { }
retrieve push_6 { }
retrieve multiply
store conditional_return_block_push_6 { }
retrieve push_1 { }
retrieve subtract jump_if_negative
{ }
quit
end
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