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5.7 URL Param

The Web Server needs to encode information in URLs. If this data is stored in the query string, than it will be overridden by browsers that make GET requests to those URLs with more query data. So, it must be encoded in URL params. This module provides functions for helping with this process.

(insert-param u k v)  url?
  u : url?
  k : string?
  v : string?
Associates k with v in the final URL param of u, overwritting any current binding for k.

(extract-param u k)  (or/c string? false/c)
  u : url?
  k : string?
Extracts the string associated with k in the final URL param of u, if there is one, returning #f otherwise.