Multidisciplinary CS: Jonathan Cottrell

WML Parser

This is a small parser for a Wiki Markup Language. It was written in JavaScript in the context of McGill's Programming Languages and Paradigms (COMP 302) as taught by Dr. Clark Verbrugge. He is the author of most of the examples shown below.

Click compile to view results.

Things to consider:
* Does your list start ok?
* Continue ok?
** At multiple levels?
**** Even deeper
* Ok that's enough
* Try all kinds and mixes, you have
*# Unordered lists
*#* like this
*#* and this
*# Ordered lists
*## like this
*## and this
*# Indented lists
*#: like this
*#: and this

That's enough

*a
*b
*#*c
*d
::e
 f
<h2>Basic tests</h2>
{:simple1||Hello:}{{simple1}}
{:simple2|x|Hello {{{x}}}:}{{simple2}}, {{simple2|there}}
{:simple3|x y|Hello {{{x}}} and {{{y}}}:}{{simple3|there}}, {{simple3|there|elsewhere}}
{{simple2|{{simple1}}}} 
{:simple2x|x|Hello {{{x|}}}:}{{simple2x}}, {{simple2x|}}, {{simple2x|there}}
<hr>

<h2>Nesting</h2>
{:foo|x|{:bar|y|{{{y}}}:}{{{x}}} and {{bar|there}}:}{{foo|here}}
{:indirect||actual:}{:actual||hello:}{{{{indirect}}}}
<hr>

<h2>Advanced Tests</h2>

<h3>Recursion</h3>
{:count|start stop|{{#ifeq|{{#expr|{{{start}}}<={{{stop}}}}}|true|{{{start}}} {{count|{{#expr|{{{start}}}+1}}|{{{stop}}}}}|}}:}{{count|1|10}} <font color="green">1 2 3 4 5 6 7 8 9 10</font><br />
{:psum|n|{{#ifeq|{{#expr|{{{n}}}<=0}}|true|0|{{#expr|{{{n}}}+{{psum|{{#expr|{{{n}}}-1}}}}}}}}:}
partial sum of 6 is {{psum|6}} <font color="green">21</font><br />
<hr>

<h3>Computation</h3>
{:times|x y|{{#expr|{{{x}}}*{{{y}}}}}:}{:square|x|{{times|{{{x}}}|{{{x}}}}}:}{:sum-of-squares|x y|{{#expr|{{square|{{{x}}}}}+{{square|{{{y}}}}}}}:}
Sum of squares is: {{sum-of-squares|3|4}} <font color="green">25</font><br />
{:abs|x|{{#ifeq|{{#expr|({{{x}}})<0}}|true|{{#expr|-({{{x}}})}}|{{{x}}}}}:}
Abs is: {{abs|4}}, {{abs|-4}} <font color="green">4, 4</font><br />
{:average|a b|{{#expr|(({{{a}}})+({{{b}}}))/2}}:}Average of 5 and 10 is {{average|5|10}} <font color="green">7.5</font><br />
{:improve|guess z|{{average|{{{guess}}}|{{#expr|{{{z}}}/{{{guess}}}}}}}:}{:good-enough?|guess x|{{#expr|{{abs|{{#expr|{{square|{{{guess}}}}}-{{{x}}}}}}}<0.001}}:}{:sqrt-iter|guess x|{{#ifeq|{{good-enough?|{{{guess}}}|{{{x}}}}}|true|{{{guess}}}|{{sqrt-iter|{{improve|{{{guess}}}|{{{x}}}}}|{{{x}}}}}}}:}{:sqrt|num|{{sqrt-iter|1|{{{num}}}}}:}
Sqrt of 49 is {{sqrt|49}}

Expected text is in green.
<h2>Anonymous templates</h2>
{:cons|a b|`{:|q|{{#ifeq|{{{q}}}|car|{{{a}}}|{{#ifeq|{{{q}}}|cdr|{{{b}}}|}}}}:}:}{:car|x|{{{{{x}}}|car}}:}{:cdr|x|{{{{{x}}}|cdr}}:}{:squares||{{cons|1|{{cons|4|{{cons|9|{{cons|16|{{cons|25|}}}}}}}}}}:}{:odds||{{cons|1|{{cons|3|{{cons|5|{{cons|7|}}}}}}}}:}{:print|x|{{#if|{{{x}}}|{{car|{{{x}}}}} {{print|{{cdr|{{{x}}}}}}}}}:}Square list: {{print|{{squares}}}}
{:nth|n x|{{#if|{{#expr|{{{n}}}==0}}|{{car|{{{x}}}}}|{{nth|{{#expr|{{{n}}}-1}}|{{cdr|{{{x}}}}}}}}}:}
The square at index 3: {{nth|3|{{squares}}}}

{:length|x|{{#if|{{{x}}}|{{#expr|1+{{length|{{cdr|{{{x}}}}}}}}}|0}}:}
Length of squares: {{length|{{squares}}}}, and odds: {{length|{{odds}}}}

{:map|list fn|{{#if|{{{list}}}|{{cons|{{{{{fn}}}|{{car|{{{list}}}}}}}|{{map|{{cdr|{{{list}}}}}|{{{fn}}}}}}}}}:}{:square|x|{{#expr|({{{x}}})*({{{x}}})}}:}{:bracket|x|({{{x}}}):}Squaring the odds: {{print|{{map|{{odds}}|square}}}}<br />
Squaring the squared odds: {{print|{{map|{{map|{{odds}}|square}}|square}}}}<br />
Brackets on the odds: {{print|{{map|{{odds}}|bracket}}}}<br />
Brackets on the squared odds: {{print|{{map|{{map|{{odds}}|square}}|bracket}}}}<br />

<h2>Nesting</h2>
{:outer|x|{:inner|x|Inner={{{x}}}:}Outer={{{x}}} {{inner|inner}}:}
{{outer|outer}}
{:scope||static:}{:showscope||You have {{scope}} scoping.:}{:dyntest||{:scope||dynamic:}{{showscope}}:}{{dyntest}}<br />

{:wrap|x|`{:||{{{x}}}:}:}
Say <font color="green">hello</font>: {{{{{{wrap|`{:||Hello:}}}}}}}<br />
Say <font color="green">hello</font> again: {{{{{{{{wrap|{{wrap|`{:||Hello:}}}}}}}}}}}<br />

<h2>Closures</h2>
{:holder1|x|{:holder2||{{{x}}}:}`{:||{{holder2}}:}:}{:holder2||Boo!:}{:v1||{{holder1|pumpkin}}:}{:v2||`{:||{{holder1|squash}}:}:}
{{{{v1}}}} is a {{{{{{v2}}}}}}

HTML code Output: