Start Language specification

PLATYPUS Grammar Specification.md

@@ -0,0 +1,95 @@
+# PLATYPUS Language Specification
+
+## Lexical Specification (INCOMPLETE)
+
+## NOTE: **This is incredibly incomplete and broken, I am simply writing this down and will fix it as I read along the informal language specification provided to me**
+
+1. Input Elements and Tokens
+```
+    <input character> ->
+        ASCII characters but not SEOF
+
+    <input> ->
+        <input elements> SEOF
+
+    <input elements> ->
+        <input element> | <input elements> <input element>
+
+    <token> ->
+        <variable identifier> | <keyword> | <floating-point literal>
+        | <integer literal> | <string literal> | <separator> | <operator>
+```
+2. White Space
+```
+    <white space> ->
+        ASCII SP character (space)
+        | ASCII HT character (horizontal tab)
+        | ASCII VT character (vertical tab)
+        | ASCII FF character (form feed)
+        | <line terminator>
+    
+    <line terminator> ->
+        CR | LF | CR LF
+```
+3. Comments
+```
+    <comment> ->
+        !< <opt_characters in line> <line terminator>
+
+    <characters in line> ->
+        <comment character> | <characters in line> <comment character>
+
+    <comment character> ->
+        <input character> but not <line terminator>
+```
+4. Variable Identifiers
+```
+    <variable identifier> ->
+        <arithmetic variable identifier> | <string variable identifier>
+
+    <arithmetic identifier> ->
+        <letter> <opt_letters or digits>
+
+    <letters or digits> ->
+        <letter or digit> | <letters or digits> <letter or digit>
+    
+    <letter> -> one of
+        [a-z][A-Z]
+
+    <letter or digit> -> one of
+        [a-z][A-Z][0-9]
+
+    <string variable identifier> ->
+        <arithmetic variable identifier># 
+```
+5. Keywords
+```
+    <keyword> ->
+        PLATYPUS | IF | THEN | ELSE | USING | REPEAT | INPUT | OUTPUT
+```
+6. Integer Literals
+```
+    <integer literal> ->
+        <decimal integer literal> | <octal integer literal>
+    
+    <decimal integer literal> ->
+        0 | <non-zero digit> <opt_digits>
+
+    <digits> ->
+        <digit> | <digits> <digit>
+
+    <digit> ->
+        0 | <non-zero digit>
+    
+    <non-zero digit> -> one of
+        [1-9]
+
+    <octal integer literal> ->
+        0 <octal digit> <octal digits>
+
+    <octal digit> ->
+        0 | 1 | 2 | 3 | 4 | 5 | 6 | 7
+    
+    <octal digits> ->
+        <octal digit> | <octal digits> <octal digit>
+