FoldIt Script Collections or Tables.

LUA refers to "Tables" where I refer to Collections and have referred to Structures.  A LUA collection contains an indexed set of objects.  The index can be either an integer or a string.  The index can be specified or assumed during construction.  A collection is constructed by a paired set of braces({ and }) .  The collection can be constructed empty or with objects in it.  Here is an empty constructor:

  x={}

The index is identified by a paired set of brackets ([ and ]).  The index will be evaluated during assignment.  A variable name is equivalent to index with it's name quoted.  When elements are indexed during construction the elements must be separated by either a comma (,) or semicolon (;).  Here the construction of a collection with named indexes:

x={[1]='first',[2]='second',['third']='value indexed by "third"',forth='value indexed by "forth"'}

A constructor can span lines.

During construction elements whose index is not specified are assigned to sequential integer indexes starting from 1.

A string index can be referenced using "dot" notation or by using normal bracket notation.  These produce the same results:

print(x.forth)
print(x['forth'])

After construction elements can be added to the collection by placing the collection and index on the left side of the equal sign (=) in an assignment statement.  Remember that the index is evaluated prior to use.  Here is a small script you can try and modify to prove your understanding:

a=4;
x={
  [1]='lookout index 1 will be overlayed',
  'implied index of 1',
  'implied index of 2',
  x='"x" masquerading as a variable';
  ["a"]='indexed by "a" can be referenced using dot notation';
  [a]='indexed by the value of a, in this case 4'
};
print('x[1]=', x[1])
print('x[2]=', x[2])
print('x["x"]=', x["x"])
print('x.a=', x.a)
print('x[4]=', x[4])

I hope you are beginning to get an idea about how FoldIt builds scripts.  A script is a collection with some special syntax.  Running a script means to evaluate the integer indexes in order.

Next time I'll cover functions and start to move into writing maintainable programs.