Give a better error message when failing pattern matching.
Give a better error message when failing pattern matching.

carymrobbins/intellij-haskforce,carymrobbins/intellij-haskforce,carymrobbins/intellij-haskforce,begray/intellij-haskforce,KasperJanssens/intellij-haskforce,begray/intellij-haskforce,charleso/intellij-haskforce,charleso/intellij-haskforce,begray/intellij-haskforce,charleso/intellij-haskforce,KasperJanssens/intellij-haskforce