[plt-planet-announce] Updated PLaneT package: plai/plai.plt for 4.x

This announces the availability of an updated package from PLaneT:

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Name:            plai.plt
Package version: 1.17
Owner:           plai


Package Description
Language levels for the Programming Languages: Application and Interpretation textbook
Release Notes
Standardize error printing in type-case Memoizing contracts from datatypes
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Go to 

http://planet.plt-scheme.org/display.ss?package=plai.plt&owner=plai

for more information.