Module lexical_util::step

The maximum digits that can be held in a u64 for a given radix without overflow.

This is useful for 128-bit division and operations, since it can reduces the number of inefficient, non-native operations.

Generation

See etc/step.py for the script to generate the divisors and the constants, and the division algorithm.

Functions

• max_step
  Calculate the maximum number of digits that can be processed without always overflowing for a given type. For example, 20 digits can be processed for a decimal string for u64 without overflowing, but it may overflow.
• min_step
  Calculate the maximum number of digits that can always be processed without overflowing for a given type. For example, 19 digits can always be processed for a decimal string for u64 without overflowing.
• u64_step
  Calculate the number of digits that can be processed without overflowing a u64. Helper function since this is used for 128-bit division.