Above you can view that the supply map is an object containing that is literal of juicy information:
- Variation quantity that the foundation map is dependent off
- The file title associated with the code that is generatedYour minifed/combined manufacturing file)
- sourceRoot lets you prepend the sources by having a folder structure – it is additionally a area preserving strategy
- sources contains all of the file names that have been combined
- names contains all variable/method names that appear throughout your rule.
- Finally the mappings home is when the miracle occurs Base64 that is using VLQ. The genuine area preserving is done right right here.
Base64 VLQ and maintaining the supply map tiny
Initially the origin map spec had a tremendously verbose production of all mappings and led to the sourcemap being about 10 times the dimensions of the code that is generated. Variation two paid down that by around 50% and variation three paid down it once again by another 50%, therefore for a 133kB file you wind up by having a
300kB supply map. Just how did they lessen the size while nevertheless keeping the complex mappings?
VLQ (Variable size amount) can be used along side encoding the worth into a Base64 value. The mappings home is an excellent string that is big. In this sequence are semicolons (;) that represent a line quantity inside the file that is generated. Within each line you will find commas (,) that represent each section within that line. Every one of these segments is either 1, four or five in variable length industries. Some can happen much longer but these have continuation bits. […]