FileFormats.md

File Formats

A documentation of the file formats read and written by this library.

• File Formats
  • Automatas
    • Course specific
      • Examples
  • Context Free Grammars
    • JFLAP
    • Course specific
      • Examples

Automatas

Course specific

This library can read a format specific to the related course, it works like this.

• One line with the alphabet, and ε if it's a ε-NFA, separated by separated by whitespace(s).
• And one line per state. Each line should contain the following information in the following order, separated by whitespace(s).
  • The UTF-8 character → or -> if this is the start state.
  • A * if this is a accepting state.
  • The name of the state. One or more non-whitespace characters.
  • Then comes the transitions, in a order corresponding to the symbols of the alphabet on the first line.
    If there are multiple transitions, as can be the case for NFAs and ε-NFAs, all transitions for one symbol should be surrounded by { }, and separated by whitespace(s). The UTF-8 character ∅ can be used to represent empty sets.

Comments are allowed, everything after a # is ignored.

Examples

A DFA:

       a  b  c
→ * s₀ s₁ s₀ s₂
    s₁ s₂ s₁ s₁
  * s₂ s₂ s₂ s₂

A NFA:

     a    b    c
→ s₀ {s₀} {s₁} {s₀ s₂}
  s₁  ∅   {s₃}  {s₂}
  s₂  ∅   {s₁}  {s₄}
  s₃ {s₄}  ∅    {s₃}
* s₄  ∅   {s₄}   ∅

And a ε-NFA:

      ε     a        b
→ s₀  ∅    {s₁}   {s₀ s₂}
  s₁ {s₂}  {s₄}     {s₃}
  s₂  ∅   {s₁ s₄}   {s₃}
  s₃ {s₅} {s₄ s₅}    ∅
  s₄ {s₃}   ∅       {s₅}
* s₅  ∅    {s₅}     {s₅}

Context Free Grammars

JFLAP

This library can read the XML file format .jff of JFLAP. This has been tested with the JFLAP 4 format.

Course specific

It can also read a format specific to the related course, it works like this.

Each production of the grammar is written on one line starting with the non-terminal "name" of the production. Followed by the UTF-8 character →. After that all the alternative of the production is listed, separated by a bar |.

Note: Non-terminals must be single uppercase letter (A-Z), all other characters are considered to be terminals with one exception. The UTF-8 character ε is used to represent the empty string.

Examples

E→EOE|N
O→+|-|ε
N→1|1N