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POpython: local variable referenced before assignment error
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copied!<p>I am completing a text based game for an intro to python class. It is not complete but I was working on the main_menu function and the functions called within the main_menu function when I ran into this error message. I have encountered this error several times in my learning experience and it was usually attributed to a basic mistake when assigning variables, but this one has me stumped... This is the script in question (lines in traceback commented in <strong>BOLD</strong>):</p> <pre><code>import random from sys import exit # Item variables coal = ('Coal', 'some coal which can be used in a furnace.') eng_key = ('Key', 'a key to a house.') bomb = ('Bomb', 'a combustible device which creates a powerfull explosion. Possibly used for demolition...') tonic = ('Tonic', 'a weak healing tonic. Adds \'5\' health points.') sTonic = ('Super Tonic', 'a strong healing tonic. Adds \'10\' health points.') # LOCATIONS # Below are the possible locations you can 'travel' to, along with a title (first item in tuple), a description, any items that might be found in the location which can be discovered and entered into 'inventory' through 'search' command # location variable = (title, description, item for discovery) sub_base = ('Sub-Base', 'This is DeepBlue\'s base of operations in the Atlantis excavation zone. Your submarine is docked ahead', 'nothing useful here.') cave = ('Underwater Cave', 'You have entered the mouth of an underwater cave with your sub.', 'nothing useful here.') cemetery = ('Cemetery Chamber', 'You are in a large chamber within the cave. This seems to be a cemetery. There are symmetrically lined mounds of dirt, with obelisks at the head.', 'nothing useful here.') city_gate = ('City Gate', 'You stand at a crossroad of sorts, at the bottom of an upward sloping ramp.', 'nothing useful here.') city_outskirts = ('City Outskirts', 'You find yourself just outside the city walls.', 'nothing useful here.') castle_outskirts = ('Rear of Castle Ruins', 'You are standing at the rear of the castle ruins. There is a layer of rubble blocking the way, but you can clearly see a passage leading inside. Perhaps you can devise a way to move it...', 'nothing useful here.') castle_inside = ('Inside the Grand Castle of Atlantis', 'You have made it inside of the castle. All the advanced knowledge of the Atlanteans is at your disposal.', 'nothing useful here.') city_block0 = ('Beginning of Main Avenue in City', 'You are standing at the beginning of the main avenue of the city.', 'nothing useful here.') ruins1 = ('Rubble of Dilapidated House', 'You are standing in the middle of the ruins of what seems to have been a house.', tonic) mystic_house = ('Mystic House', 'You are standing inside the city Mystic\'s house.', sTonic) city_block1 = ('Second Block in City', 'You have moved to the second block of the city\'s main avenue.', 'nothing useful here.') abandoned_house = ('Abandoned House', 'You are standing in the middle of an abandoned house.', eng_key) blacksmith_house = ('Blacksmith\'s House', 'You are standing in what seems to be a blacksmith\'s building. There is a furnace, iron ore, smith\'s tools and various components for making swords. No coal though...', 'nothing useful here. But with the right items, something can be created here...') city_block2 = ('Third Block in City', 'You have moved to the third block of the city\'s main avenue.', 'nothing useful here.') marketplace = ('Abandoned Marketplace', 'You are standing in the middle of an abandoned marketplace. There might be some useful items laying around...', coal) engineer_house = ('Engineer\'s House', 'You are standing in the engineer\'s house. There might be some useful items lying around...', bomb) castle_main = ('Castle Main Entrance', 'You are standing in front of the main entrance of a huge castle. The grand entrance is blocked off by massive amounts of rubble. There must be another way in...', 'nothing useful here.') # ITEMS # below are the items which may be added to the inventory items = { coal: (engineer_house,), eng_key: (engineer_house,), bomb: (castle_inside,), tonic: ('anywhere',), sTonic: ('anywhere',) } # INTERACTIONS(location-based) # below is a dictionary of events. Each location has certain events which can only take place there. # interactions dictionary = {location: (use+item response, search response)} lEvents = {sub_base: (cave,), cave: (sub_base, cemetery, city_gate), cemetery: (cave, city_outskirts), city_gate: (cave, city_outskirts, city_block0), city_outskirts: (cemetery, castle_outskirts, city_gate), castle_outskirts: (city_outskirts,castle_inside), castle_inside: (castle_outskirts,), city_block0: (city_gate, ruins1, mystic_house, city_block1), ruins1: (city_block0,), mystic_house: (city_block0,), city_block1: (city_block0, abandoned_house, blacksmith_house, city_block2), abandoned_house: (city_block1,), blacksmith_house: (city_block1,), city_block2: (city_block1, marketplace, engineer_house, castle_main), marketplace: (city_block2,), engineer_house: (city_block2,), castle_main: (city_block2,) } # TRAVEL OPTIONS # Below is a dictionary outlining the possible places to travel to depending on where you are currently located, this peice is essential to the travel function travelOpt = { sub_base: (cave,), cave: (sub_base, cemetery, city_gate), cemetery: (cave, city_outskirts), city_gate: (cave, city_outskirts, city_block0), city_outskirts: (cemetery, castle_outskirts, city_gate), castle_outskirts: (city_outskirts,castle_inside), castle_inside: (castle_outskirts,), city_block0: (city_gate, ruins1, mystic_house, city_block1), ruins1: (city_block0,), mystic_house: (city_block0,), city_block1: (city_block0, abandoned_house, blacksmith_house, city_block2), abandoned_house: (city_block1,), blacksmith_house: (city_block1,), city_block2: (city_block1, marketplace, engineer_house, castle_main), marketplace: (city_block2,), engineer_house: (city_block2,), castle_main: (city_block2,) } def eHouseAccess(action, location, eHouse): if eHouse == 'locked': print "The door is locked! You need to find a key for this door." travel(location) else: location = travelOpt[location][action - 1] travel(location) def cInsideAccess(action, location, cInside): if cInside == 'blocked': print "The path is blocked by rubble! You need to find a way to clear the rubble." travel(location) else: location = travelOpt[location][action - 1] travel(location) def travel(location): while True: print "You are in the", location[0]+"." print location[1] print 'You can travel to:' for (i, t) in enumerate(travelOpt[location]): print i + 1, t[0] action = raw_input("Pick a destination, or enter 'menu' for the main menu: ") if action == 'menu': main_menu(location, inventory, items) else: action = int(action) if travelOpt[location][action - 1] == engineer_house: eHouseAccess(action, location, eHouse) elif travelOpt[location][action - 1] == castle_inside: cInsideAccess(action, location, cInside) else: location = travelOpt[location][action - 1] def main_menu(location, inventory, items): travel = travel(location) # **this is line 133** invtry = showInv(inventory) use = use(items, inventory) quit = exit(0) while True: print "You are in the", location[0] menu_list = [('Travel', travel), ('Inventory', invtry), ('Use', use), ('Search', search), ('Map', map), ('Quit', quit)] print "Choose one:" for (num, t) in enumerate(menu_list): print num + 1, t[0] main_choice = int(raw_input("> ")) action = menu_list[main_choice - 1] action[1] def search(location): pass def map(location): pass def showInv(inventory): if inventory == []: print "Your inventory is empty" inv = 'empty' return inv else: for (num, i) in enumerate(inventory): print num + 1, i inv = inventory return inv def use(items, inventory): a = showInv(inventory) if a == 'empty': print "There is nothing to use." else: showInv(inventory) uItem = int(raw_input("Choose an item to use: ")) location = sub_base inventory = [] eHouse = 'locked' cInside = 'blocked' hp = 20 map = """ Key: * = indicates a point of entry ______ ______ |Castle|Castle| |Outsk-| | |irts | ___|**____|__**__| | City | | | |Outsk-| | City | | irts | | | _____|*____*|___|*_____| | | | | | Grave | | City | | Yard | | Gates | |_____**|__|*______| | | | Cave | | | |__**___| | | | Sub- | | Base | |_______| """ cityMap = """ Key: * = indicates a point of entry ________ | | | Castle | | | ______|___**___|________ | | City | Engin- | |Market| Block | eer | |Place * 3 * House | |______|___ ___|________| |Aband-| City | Black- | | oned | Block | smith | |House * 2 * House | |______|___**___|________| | | City | | |Rubble| Block |Mystic's| | * 1 * House | |______|________|________| """ name = raw_input("Enter your name: ") print "Welcome to the Atlantis Excavation Zone, %s." % name print "Your first day on the job and we already have a new cave for you to map... LUCKY!" print "The DeepBlue team takes you down to the sub base. Time to get to work." main_menu(location, inventory, items) # **this is line 236** </code></pre> <p>And here is the traceback:</p> <pre><code>Traceback (most recent call last): File "ex36_2.py", line 236, in <module> main_menu(location, inventory, items) File "ex36_2.py", line 133, in main_menu travel = travel(location) UnboundLocalError: local variable 'travel' referenced before assignment </code></pre> <p>I thought the variable had been assigned in line 133. What am I missing here?</p>

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