hex.input_dec_int

dst[:n] = the signed decimal number read from input (two’s complement, mod 16^n).
Reads an optional leading ‘-’, then ASCII ‘0’..’9’ until a ‘\n’ or ‘\0’ (EOF)
terminator; jumps to error on any other byte. Inverse of hex.print_dec_int.

Signature

def input_dec_int n, dst, error @ sign_hi, minus, loop, valid_hi, terminator, digit_char, add_digit, finish, digit, byte, neg, end { ... }

Defined in hex/input.fj — lines 132–167 (view on GitHub).

Complexity

• Time: ~ d(n(10@+39)) + (d+1)(7@+11) + @+4n    (d = number of digits; estimate)

• Space: ~ n(10.5@+149) + 10@+130                (estimate)

See the complexity glossary for what @, w, dw, dbit, n mean.

Requires init

The following must be initialised before this macro is invoked:

• hex.init

Source

Click to view the macro body

def input_dec_int n, dst, error @ sign_hi, minus, loop, valid_hi, terminator, digit_char, add_digit, finish, digit, byte, neg, end {
    .zero n, dst
    .zero n, digit
    bit.zero neg
    .input byte
    .if_flags byte+dw, 1<<2, loop, sign_hi            // high nibble 2 -> maybe '-'
  sign_hi:
    .if_flags byte, 1<<0xD, error, minus              // '-' is 0x2D
  minus:
    bit.not neg
    .input byte
  loop:
    .if_flags byte+dw, (1<<0)|(1<<3), error, valid_hi
  valid_hi:
    .if_flags byte+dw, 1<<3, terminator, digit_char
  terminator:
    .if_flags byte, (1<<0x0)|(1<<0xA), error, finish
  digit_char:
    .if_flags byte, (1<<10)-1, error, add_digit
  add_digit:
    .mul10 n, dst
    .zero digit
    .xor digit, byte
    .add n, dst, digit
    .input byte
    ;loop
  finish:
    bit.if0 neg, end
    .neg n, dst
    ;end

  digit: hex.vec n
  byte:  hex.vec 2
  neg:   bit.bit
  end:
}

Depends on

• bit.if0/2

• bit.not/1

• bit.zero/1

• hex.add/3

• hex.if_flags

• hex.input/1

• hex.mul10

• hex.neg

• hex.xor/2

• hex.zero/1

• hex.zero/2

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