00.1 - Of functions and modules.ipynb

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    "square x = x ** 2"
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    "square 10"
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   "metadata": {},
   "source": [
    "# Modules"
   ]
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   "source": [
    "Loading a function from a file `baby.hs` which contains a function `doubleMe`"
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   "outputs": [],
   "source": [
    ":l baby"
   ]
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    "doubleMe 4"
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    "doubleMe pi"
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   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Creating higher level functions"
   ]
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   "outputs": [],
   "source": [
    "doubleSum x y = doubleMe x + doubleMe y"
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    "doubleSum 10 20"
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    "doubleSum 1 2 + doubleSum 10 12"
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   "source": [
    "* Functions in Haskell don't have to be in any particular order\n",
    "* Functions can be redefined"
   ]
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   "cell_type": "code",
   "execution_count": 23,
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   "source": [
    "doubleMe x = x * 3\n",
    "\n",
    "doubleSum x y = doubleMe x + doubleMe y"
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    "doubleSum 10 20"
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   "cell_type": "code",
   "execution_count": 26,
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   "outputs": [],
   "source": [
    ":l baby.hs"
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   "cell_type": "markdown",
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   "source": [
    "# If-else statement"
   ]
  },
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   "cell_type": "code",
   "execution_count": 27,
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   "outputs": [],
   "source": [
    "doubleSmallNumber x = if x > 100\n",
    "                         then x\n",
    "                         else x * 2"
   ]
  },
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   "source": [
    "* else part is mandatory in Haskell\n",
    "* if-else statement is an expression as it always returns something"
   ]
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   "execution_count": 10,
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       "101"
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    "doubleSmallNumber 101"
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    "doubleSmallNumber 99"
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    "doubleSmallNumber' x = (if x > 100 then x else x * 2) + 1"
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       "102"
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    "doubleSmallNumber' 101"
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   "source": [
    "Apostrophe `'` is a valid character in a function name. Usually denoted to write a strict (non-lazy) version or a modified version."
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       "<style>/* Styles used for the Hoogle display in the pager */\n",
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       "}\n",
       ".suggestion-name {\n",
       "font-weight: bold;\n",
       "}\n",
       "</style><div class=\"suggestion-name\" style=\"clear:both;\">Use camelCase</div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Found:</div><div class=\"highlight-code\" id=\"haskell\">conanO'Brien = ...</div></div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Why Not:</div><div class=\"highlight-code\" id=\"haskell\">conanOBrien = ...</div></div>"
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       "Line 1: Use camelCase\n",
       "Found:\n",
       "conanO'Brien = ...\n",
       "Why not:\n",
       "conanOBrien = ..."
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    "conanO'Brien = \"It's a-me, Conan O'Brien!\"   "
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    "* This is also a function with no input parameters\n",
    "* The convention is to use camelCase, although not strictly\n",
    "* Functions can't begin with uppercase"
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       ".suggestion-name {\n",
       "font-weight: bold;\n",
       "}\n",
       "</style><div class=\"suggestion-name\" style=\"clear:both;\">Use camelCase</div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Found:</div><div class=\"highlight-code\" id=\"haskell\">snake_case = ...</div></div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Why Not:</div><div class=\"highlight-code\" id=\"haskell\">snakeCase = ...</div></div>"
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       "Line 1: Use camelCase\n",
       "Found:\n",
       "snake_case = ...\n",
       "Why not:\n",
       "snakeCase = ..."
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    "snake_case = \"Harrrrry pott-ahhhhh\""
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