Tom Leidy
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tomleidy.bsky.social
Tom Leidy
@tomleidy.bsky.social
6 followers 10 following 38 posts
interests: facets of creation; language, art, emotion, thoughts, systems, science, and technology. communication and community.

longing for the San Francisco that exists in my mind and heart (from before the pandemic).
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tomleidy.bsky.social
Tired of fumbling through which is which, I made these tables to understand expansion (for my primary use case) better. Hopefully I’ll remember I left this here. #shell #scripting #shellscripting #bash #expansion
Table 1: Remove shortest length string starting from left, use #. From right? Use %. To remove longest length string starting from left, use ##, with %% for from the right. Table 2: The various combinations of expansions and wildcard/period placement for extracting file stem and suffix. Most do not work. To extract file name/stem from shell expansion, use %.* and to extract the suffix, use ##*.
August 28, 2025 at 5:26 PM
tomleidy.bsky.social
OK, learning C. Again.

The 1st time I thought pointers were easy.

The 2nd, "I remember this!"

The 3rd, "did I ever understand these at all?"

I listened to and read explanations and got more confused.

Turned out explanation was too much.

Concise syntax reminders? Got it. #cheatsheet #C
Screenshot of a markdown table concisely displaying the differences between different C variable syntaxes as they relate to pointers. If you want the text, please let me know!
July 31, 2025 at 8:05 PM
tomleidy.bsky.social
I did a coding challenge for an interview pre-screen yesterday, and I couldn’t remember the JS RegExp syntax. I used string methods, but… I figured it out after. This morning, I compared the performance of regex to string methods for parsing JSON.

Anyway, yay regex!
Chart comparing the performance of regular expressions and JS string/array methods for parsing increasing string lengths, with them starting out with similar durations at shorter lengths but regex remains below 1000ms for the entire graph while string and array methods reach over 3000ms (last data point is approximately 92 million bytes) on an M1 Macbook Pro Snippet of JavaScript using Regular Expressions: start = performance.now(); // timing start let pattern = /key=([\w]+)/g let matches = jsonContent.data.matchAll(pattern); for (const match of matches) { keyArray.push(match[1]); } end = performance.now(); // timing stop Snippet of JavaScript using string and array methods: start = performance.now(); // timing start let jsonContentArray = jsonContent.data.split(', '); for (let i = 0; i < jsonContentArray.length; i++) { let key = jsonContentArray[i].split('='); if (key[0] == 'age') continue; keyArray.push(key[1]); } end = performance.now(); // timing stop
May 6, 2025 at 5:15 PM
tomleidy.bsky.social
A friend was working on parsing strings for D&D / dice rolling where she was doing her own string parsing. It was a little challenging to read that way, and she definitely optimized it.

I needed to satisfy my curiosity about how to do it with regular expressions, and this is what I came up with.
Python code: import re def parse_dice_roll(dice_roll: str) -> tuple[int]: """Dice roll string parsing: Argument: 'XdY x Z' or 'XdY' strings where X, Y, and Z are integers Return: (X, Y, Z) or (X, Y) tuples""" dice_pattern = r"(\d+)d(\d+)(?:\sx\s(\d+))?" if re.match(dice_pattern, dice_roll): capture_groups = re.findall(dice_pattern, dice_roll, re.IGNORECASE) return tuple(int(group) for group in capture_groups[0] if group) return None
March 17, 2025 at 2:46 PM