Show HN: CoordConversions NPM Module for Map Coordinate Conversions

New map tool sparks ‘lon vs lat’ showdown — devs pick sides

TLDR: A new TypeScript tool converts map coordinates cleanly, but the comments fixate on one question: should it return longitude before latitude to match GeoJSON? The crowd pushes for lon/lat to prevent bugs, sparking the classic map-order flamewar that matters because swapped numbers break apps and send pins astray.

A new CoordConversions module hit Show HN, promising to convert map coordinates between simple numbers and old-school formats, and even handle hemispheres. But the spotlight instantly swung to the spiciest question in geo-land: which number comes first? One early commenter waved the red flag: GeoJSON prefers [longitude, latitude], so can this library return lon-before-lat to save everyone from fiascos? Cue eye-rolls, knowing laughs, and the ritual summoning of the “classic geo-flamewar.”

People joked about careers ruined by swapped numbers, maps flipped inside out, and delivery drivers rerouted to the ocean. The vibe: love the library’s strict parsing and validation, but please pick a default that doesn’t burn developers. The strongest opinion: make lon/lat the default, or at least make it impossible to get wrong. The soft counterargument: just be consistent and document clearly. Meanwhile, memes rained down—“Team Lon-first” vs “Lat-first Lifers”—and everyone agreed on one thing: if this tool nails formatting and flags mistakes, it could save countless midnight debugging sessions. The drama isn’t the math—it’s the order.

Quick explainer: DD is plain decimals, DM adds minutes, and DMS uses degrees, minutes, seconds—like a clock for places. Hemisphere labels keep north/south and east/west straight. Now just decide the order.

Key Points

  • CoordConversions is a TypeScript library for coordinate format conversion.
  • It supports Decimal Degrees (DD), Degrees–Minutes (DM), and Degrees–Minutes–Seconds (DMS).
  • The library includes parsing to interpret inputs across supported formats.
  • It provides validation and formatting utilities for consistent coordinate output.
  • It supports hemisphere indicators to correctly handle N/S and E/W designations.

Hottest takes

"do you consider returning the DD coordinates as [longitude, latitude]?" — pheelicks
"Getting these backwards is a common frustration" — pheelicks
"my vote would be for Lon/lat ordering" — pheelicks
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