lambdaway :: meta

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_h2 meta | [[meta2]] | [[meta3]] | [[meta4]] | [[meta5]]

_p Building a tinytalk in lambdatalk, a kind of meta circularity.

_h2 code

{pre
'{def rex $([^\s()]*)(?:[\s]*)([^()]*)$}
-> {def rex $([^\s()]*)(?:[\s]*)([^()]*)$}

'{def apply {lambda {:f :r} <:f>:r< /:f>}}
-> {def apply {lambda {:f :r} <:f>:r</:f>}}

'{def eval
 {def eval.r
  {lambda {:n :x}
   {if {> :n 0}
    then {S.replace {rex} 
                 by {apply $1 $2}  
                 in {eval.r {- :n 1} :x}} else :x}}}
 {lambda {:x} {eval.r {S.length :x} :x}}}  
-> {def eval
 {def eval.r
  {lambda {:n :x}
   {if {> :n 0}
    then {S.replace {rex} 
                 by {apply $1 $2} 
                 in {eval.r {- :n 1} :x}} else :x}}}
 {lambda {:x} {eval.r {S.length :x} :x}}}
}

_h2 tests

{pre
'{eval (h1 I am a title level 1)}
}
{eval (h1 I am a title level 1)}
 
{pre
'{eval (p (b hello (i brave) (sub new) and (sup amazing) world).)} 
} 
{eval (p (b hello (i brave) (sub new) and (sup amazing) world).)}

{pre
'{eval
(table
 (tr (td .) (td one) (td two) (td three))
 (tr (td one) (td 11) (td 12) (td 13))
 (tr (td two) (td 21) (td 22) (td 23))
 (tr (td three) (td 31) (td 32) (td 33))  
)} 
} 
{eval
(table
 (tr (td .) (td one) (td two) (td three))
 (tr (td one) (td 11) (td 12) (td 13))
 (tr (td two) (td 21) (td 22) (td 23))
 (tr (td three) (td 31) (td 32) (td 33)) 
)}

{pre
'{eval
(ol 
 (li I am (del deleted)) 
 (li I am a vector a(sup i))
 (li I am a vector a(sub j)) 
)} 
}
{eval
(ol 
 (li I am (del deleted)) 
 (li I am a vector a(sup i))
 (li I am a vector a(sub j))
)}

{pre
'{eval
(dl
 (dt b) (dd boldify some text)
 (dt i) (dd italicize some text)
 (dt u) (dd underline some text)  
)}
}
{eval
(dl
 (dt b) (dd boldify some text)
 (dt i) (dd italicize some text)
 (dt u) (dd underline some text)
)}

{pre
'{eval (hr)} 
}
{eval (hr)}

{pre
'{eval (center I am centered)}
} 
{eval (center I am centered)}

_p Notes:
_ul works only on expressions built on HTML tags without attributes, 
_ul doesn't works on arithmetical expressions, {del (sqrt (+ (* 3 3) (* 4 4)))}
_ul no special forms (lambda, def, if, ...), {del (def add (lambda (:a :b) (+ :a :b)))}
_ul some CSS rules have been defined below.

{pre
'{style 
dt { font:bold 1.2em arial; color:red; }
dd { font:italic 1.0em courier; color:blue; }
tr:first-child { font:bold 1.2em arial; color:red; } 
td:first-child { font:bold 1.2em arial; color:green; }
li { font:bold 1.2em arial; color:red; } 
}

}

{style 
dt { font:bold 1.2em arial; color:red; }
dd { font:italic 1.0em courier; color:blue; }
tr:first-child { font:bold 1.2em arial; color:red; } 
td:first-child { font:bold 1.2em arial; color:green; }
li { font:bold 1.2em arial; color:red; } 
}