fixed Lisra syntax and semantics table

Author: jurgenvinju

courses/Recipes/Languages/Lisra/Lisra.md

@@ -36,52 +36,15 @@ The Lisp variant to be implemented is the following subset of the [Scheme](http:
 
 | Form | Syntax | Semantics and Example |
 | --- | --- | --- |
-| [variable reference](http://www.schemers.org/Documents/Standards/R5RS/HTML/r5rs-Z-H-7.html#%_sec_4.1.1) |
-| _var_ |
-| A symbol is interpreted as a variable name; |
-  its value is the variable's |
-  value. Example: `x` |
-| [constant literal](http://www.schemers.org/Documents/Standards/R5RS/HTML/r5rs-Z-H-7.html#%_sec_4.1.2) |
-| _number_ |
-| A number evaluates to itself. Example: `12` |
-| [quotation](http://www.schemers.org/Documents/Standards/R5RS/HTML/r5rs-Z-H-7.html#%_sec_4.1.2) |
-| `(quote exp)` |
-| Return the _exp_ literally; do not evaluate it. Example: |
-  `(quote (a b c)) =>; (a b c)` |
-| [conditional](http://www.schemers.org/Documents/Standards/R5RS/HTML/r5rs-Z-H-7.html#%_sec_4.1.5) |
-| `(if _test conseq alt_)` |
-| Evaluate _test_; if true, |
-  evaluate and return _conseq_; otherwise evaluate and return  |
-  _alt_. <br />Example: `(if (< 10 20) (+ 1 1) (+ 3 3)) => 2` |
-| [assignment](http://www.schemers.org/Documents/Standards/R5RS/HTML/r5rs-Z-H-7.html#%_sec_4.1.6) |
-| `(set! _var exp_)` |
-| Evaluate _exp_ and assign that value to |
-  _var_, which must have been previously defined (with a |
-  `define` or as a parameter to an enclosing procedure). |
-   Example: `(set! x2 (* x x))` |
-| [definition](http://www.schemers.org/Documents/Standards/R5RS/HTML/r5rs-Z-H-8.html#%_sec_5.2) |
-| `(define var exp)` |
-| Define a new variable in the innermost environment and give it |
-  the value of evaluating the expression _exp_.  |
-  Examples: `(define r 3)` or `(define square (lambda (x) (* x x)))` |
-| [procedure](http://www.schemers.org/Documents/Standards/R5RS/HTML/r5rs-Z-H-7.html#%_sec_4.1.4) |
-| `(lambda (_var..._) exp)` |
-| Create a procedure |
-  with parameter(s) named _var..._ and the expression as the body. |
-  Example: `(lambda (r) (* r r))` |
-| [sequencing](http://www.schemers.org/Documents/Standards/R5RS/HTML/r5rs-Z-H-7.html#%_sec_4.2.3) |
-| `(begin _exp..._)` |
-| Evaluate each of the expressions in left-to-right order, and return the final value. |
-  Example: `(begin (set! x 1) (set! x (+ x 1)) (* x 2)) => 4 |
-| [procedure call](http://www.schemers.org/Documents/Standards/R5RS/HTML/r5rs-Z-H-7.html#%_sec_4.1.3) |
-| `(_proc exp..._)` |
-| If _proc_ is |
-   anything other than one of the symbols `if`, `set!`, `define`, |
-   `lambda`, `begin`, or `quote` then it is treated as a procedure.  It is |
-   evaluated using the same rules defined here. All the expressions |
-   are evaluated as well, and then the procedure is called with the list |
-   of expressions as arguments.  |
-   Example: <`(square 12) => 144 |
+| [variable reference](http://www.schemers.org/Documents/Standards/R5RS/HTML/r5rs-Z-H-7.html#%_sec_4.1.1) | _var_ | A symbol is interpreted as a variable name; its value is the variable's value. Example: `x` |
+| [constant literal](http://www.schemers.org/Documents/Standards/R5RS/HTML/r5rs-Z-H-7.html#%_sec_4.1.2) | _number_ | A number evaluates to itself. Example: `12` |
+| [quotation](http://www.schemers.org/Documents/Standards/R5RS/HTML/r5rs-Z-H-7.html#%_sec_4.1.2) | `(quote exp)` | Return the _exp_ literally; do not evaluate it. Example: `(quote (a b c)) =>; (a b c)` |
+| [conditional](http://www.schemers.org/Documents/Standards/R5RS/HTML/r5rs-Z-H-7.html#%_sec_4.1.5) | `(if _test conseq alt_)` | Evaluate _test_; if true, evaluate and return _conseq_; otherwise evaluate and return _alt_. Example: `(if (< 10 20) (+ 1 1) (+ 3 3)) => 2` |
+| [assignment](http://www.schemers.org/Documents/Standards/R5RS/HTML/r5rs-Z-H-7.html#%_sec_4.1.6) | `(set! _var exp_)` | Evaluate _exp_ and assign that value to _var_, which must have been previously defined (with a  `define` or as a parameter to an enclosing procedure). | Example: `(set! x2 (* x x))` |
+| [definition](http://www.schemers.org/Documents/Standards/R5RS/HTML/r5rs-Z-H-8.html#%_sec_5.2) | `(define var exp)` | Define a new variable in the innermost environment and give it the value of evaluating the expression _exp_.   Examples: `(define r 3)` or `(define square (lambda (x) (* x x)))` |
+| [procedure](http://www.schemers.org/Documents/Standards/R5RS/HTML/r5rs-Z-H-7.html#%_sec_4.1.4) | `(lambda (_var..._) exp)` | Create a procedure with parameter(s) named _var..._ and the expression as the body. Example: `(lambda (r) (* r r))` |
+| [sequencing](http://www.schemers.org/Documents/Standards/R5RS/HTML/r5rs-Z-H-7.html#%_sec_4.2.3) | `(begin _exp..._)` | Evaluate each of the expressions in left-to-right order, and return the final value.  Example: `(begin (set! x 1) (set! x (+ x 1)) (* x 2)) => 4 |
+| [procedure call](http://www.schemers.org/Documents/Standards/R5RS/HTML/r5rs-Z-H-7.html#%_sec_4.1.3) | `(_proc exp..._)` | If _proc_ is anything other than one of the symbols `if`, `set!`, `define`, `lambda`, `begin`, or `quote` then it is treated as a procedure.  It is evaluated using the same rules defined here. All the expressions are evaluated as well, and then the procedure is called with the list of expressions as arguments.  Example: <`(square 12) => 144 |
 
 
 In this table, _var_ must be a symbol--an identifier such as x or square--and number must be an integer number,