form_design.txt

- Language intended to make it easy to create dialog boxes to help
  fill out tax forms.
- Input boxes appear left-to-right; commands for "new line" and "new
  page" (wizard interface).
- Language supports lists ("Add"/"Edit"/"Remove" buttons to modify)
- Language supports radio buttons as demonstrated below.
- Language supports forwarding the summation of entries in list and
  length of lists to output file as demonstrated below.
- Language supports doing calculations in Taxicality language,
  although this should be discouraged except for lists, where it's
  necessary.
- Type words are SLINE, NLINE, CHECK, RADIO, and LIST.
- There's also TAXICALITY.  In the example, below, the line executed
  by the interpreter might be:
  D4_Credit_Amount = D4_Child_Tax_Credit * 1000
- NLINE and CHECK convert to type NUMBER in Taxicality.

Output:
- The form is read and it generates a wizard.  After the user finishes
  the wizard, two output files are generated, one to be input for
  Taxicality and one to be input for flpsed or whatever.
- Variables from taxicality are also needed as inputs to flpsed, of
  course.  Some marshaling will be necessary.

Notes:
- For the corner case where it's necessary to generate a page of data
  from whole cloth, like when someone has more than four dependents,
  a list is used to generate a table.  The whole cloth form must
  specify which portion of the end of the list should be used to fill
  in the table, and must specify the names of the variables used
  inside of the list.

Implementation:
- No need to make a parser for this; just read it line-by-line and
  split the line into tokens.
- When creating an element in the wizard, check any saved data (stored
  in a symbol table) to see if it should be pre-filled.
- Fl_Wizard should do nicely.

Example:

Name = Name = SLINE "Your legal name"
Address = Address = SLINE "Your legal address"
newline()
SSN = SSN = SLINE "Your social security number"
newline()
RADIO "Select your filing status"
  {
    1040.L1 = Single = CHECK "Select if you are single"
    1040.L2 = Married Filing Jointly = CHECK "Select if you are married filing jointly"
  }
newline()
Deplist = LIST "List of dependents"
  {
    D#_Name = Name = SLINE "Enter dependent's name"
    D#_SSN = SSN = SLINE "Enter dependent's Social Security Number"
    D#_REL = Relationship = SLINE "Enter dependent's relationship to you"
    D#_Child_Tax_Credit = Child Tax Credit = CHECK "Does this child qualify for the child tax credit?"
    D#_Credit_Amount = Hidden Anyway = TAXICALITY "D#_Child_Tax_Credit * 1000"
  }
1040.dependents = LEN(Deplist)
1040.qualifying_children = SUM(Deplist.D#_Child_Tax_Credit)
newline()