Configuration Files
This page cover’s Hugo’s ability to write individual values to file (from which it can be read later). Games like Future Boy! and Cryptozookeeper use this to save game options such as color schemes and verbosity, but this is yet another feature where one is only limited by his or her imagination. One of the more obvious uses would be to write a couple games that use the same configuration file so that player stats or inventory carry over from one to the next.
writefile
The first thing one needs to do is to create the configuration file. For interpreters that support it, it’ll appear in the working directory (in Windows 7, for instance, it’s C:\Users\USER_NAME\AppData\Local\VirtualStore\Program Files (x86)\Hugo).
writefile "configuration_filename"
{
! we'll get to this next
}
writeval
Now, inside the block, we’ll save our values using the writeval
statement. writeval can be used to save variables, property values,
etc.
writefile "hugo_revenge_config"
{
writeval verbosity ! writes current verbosity value
writeval (dwarf_treasure is known) ! writes true (1) if statement in parentheses is true, otherwise writes false (0)
}
readfile
To read from the previously created file, we use the readfile
statement:
readfile "configuration_filename"
{
! Bet you can't guess what goes here
}
readval
The readfile block will have the same number of readvals as there
were writevals. Using the writefile as a guide, we can reset all of
our global values or settings:
readfile "hugo_revenge_config"
{
verbosity = readval ! sets verbosity to the first readval value
if readval
dwarf_treasure is known ! since there is a value in the second slot, we know that the dwarf_treasure object was known
else
dwarf_treasure is not known
}
FILE_CHECK
As the number of values in the configuration file increases, the easier
it’ll be to make mistakes. There isn’t any way for writeval and
readval to report errors, so it is recommended to use the
hugolib.h-defined
constant FILE_CHECK, like such:
routine SaveConfig
{
local test
writefile "hugo_revenge_config"
{
writeval verbosity
writeval (dwarf_treasure is known)
test = FILE_CHECK
writeval test
}
if test ~= FILE_CHECK ! if the program didn't get this far, we know something is wrong
print "An error as occurred."
}
routine LoadConfig
{
local test
readfile "hugo_revenge_config"
{
verbosity = readval
if readval
dwarf_treasure is known
else
dwarf_treasure is not known
test = readval
}
if test ~= FILE_CHECK
print "Error reading file."
}
We make sure to use FILE_CHECK for the last read and write value, so
if we accidentally skip a value somewhere along the way, the test
variable will have the wrong value and we’ll know something is wrong.
More Help
Roodylib has a “configuration file helper” extension that attempts to make some aspects of using configuration files easier.
Sharing Strings Between Two Games (Hugo Homework)
The Hugo Book lists dictionary entries among the things that writeval
can save. The important thing to remember, though, is that it saves the
dictionary entry address, not the string itself. What this means is
that if you wrote two games that shared the same configuration file,
something like writeval “apple” will not be helpful, as “apple” will
almost certainly have a different address in each game.
The question is, how do we get around this?