Your Type System Working For You!

on YouTube ↗31m

" summary

Shows how Scala turns CRS errors into compile-time guarantees by baking CRS definitions and transforms into types and implicits, using GeoTools to load EPSG models and mapping lat/longs and UTM zones to type classes. Demonstrates case-class + companion tricks, variance/invariance, existential type injection for loaded files, and compile-time rejection of mixing EPSG:4326 with UTM without a transform. Also covers raster grid coverage handling and statically typed attribute maps via TMap to prevent runtime surprises.

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" chapters (7)

1. 0:00Start
2. 3:22WGS 84 UTM Zones
3. 6:40CRS Types! Let's start with a simple definition
4. 11:28Geometries have the CRS as part of the type
5. 12:18Now, the compiler has your back
6. 16:03Reifying the CRS type from the existential
7. 19:44Grid Coverages (Rasters)

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