8_a_1: Add solution

1 files changed, 23 insertions, 0 deletions

diff --git a/ch08/8_a_1.hs b/ch08/8_a_1.hs
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+-- Use ghci to explore what happens if you pass a malformed pattern, such as [,
+-- to globToRegex. Write a small function that calls globToRegex, and pass it a
+-- malformed pattern. What happens?
+
+-- When trying to load the GlobRegex.hs file into ghci, I got an error about
+-- that the module was not found. I used Hoogle (https://hoogle.haskell.org/) to
+-- search for Text.Regex.Posix module and found it was in regex-posix package. I
+-- use stack, so I installed the package by
+--
+--   stack install regex-posix
+
+import GlobRegex
+
+callGlobToRegex glob = globToRegex glob
+
+-- ghci> :l 8_a_1.hs
+-- [1 of 2] Compiling GlobRegex        ( GlobRegex.hs, interpreted )
+-- [2 of 2] Compiling Main             ( 8_a_1.hs, interpreted )
+-- Ok, two modules loaded.
+-- ghci> callGlobToRegex "["
+-- "^*** Exception: unterminated character class
+-- CallStack (from HasCallStack):
+--   error, called at ./GlobRegex.hs:27:31 in main:GlobRegex