php/e19Closure.php

<?php
require_once('env.php');
outBegin("php closure");
outH('call functions');
outUL('before first call');
outLi("function_exists", function_exists('inF'));
f('1. call von f');
echo "<li> function_exists " . function_exists('inF') . "</li>\n";
inF('2. call von inF');
$gVar = 'gVarEins';
$gArr = ['gArr 0'];
$af = function ($a) use ($gVar, $gArr) {
    outLi("call of anonymous function in af($a) use gVar = $gVar, gArr[0] $gArr[0] count=" . count($gArr));
    };
$ag = function ($a) {
    global $gVar, $gArr;
    outLi("call of anonymous function in ag($a) global gVar = $gVar, gArr[0] $gArr[0] count=" . count($gArr));
    };
$af("3. call af");
$ag("4. call ag");
$gVar = 'gVarZwei';
$gArr[0] .= " zwei";
$gArr[1] = "1 zwei";
$af("5. call af nach assign gVar=$gVar");
$ag("6. call ag nach assign gVar=$gVar");

outULEnd("after last call");

outH('nested function');
outUL();
$nestCnt = 0;
$q1 = nest('nestOne');
$q1[0]('mainCalls' . ++$nestCnt);
$q1[1]('mainCalls' . ++$nestCnt);
$q2 = nest('nestTwo');
$q1[0]('mainCalls' . ++$nestCnt);
$q2[1]('mainCalls' . ++$nestCnt);
$q1[1]('mainCalls' . ++$nestCnt);
$q2[0]('mainCalls' . ++$nestCnt);
outULEnd();

function f ($a) {
    outLi("call of f($a)");
    function inF($b)  {
    outLi("call of inF($b)");
    }
}

function nest ($a) {
    global $nestCnt;
    outLi("runNest($a)", ++$nestCnt);
    $v = "useVal $a $nestCnt:";
    $r = "useRef $a $nestCnt:";
    $q = [function ($b) use($a, $v ,&$r)  {
                global $nestCnt;
                outLi("run-$a-NestB($b)" , ++$nestCnt, "v=$v, r=$r, appending B$nestCnt");
                $v .= ".B$nestCnt";
                $r .= ".B$nestCnt";
            },
          function ($b) use($a, $v ,&$r)  {
                global $nestCnt;
                outLi("run-$a-NestC($b)" , ++$nestCnt, "v=$v, r=$r, appending C$nestCnt");
                $v .= ".C$nestCnt";
                $r .= ".C$nestCnt";
            }
        ];
    outLi("nest($a)", ++$nestCnt, "v=$v, r=$r, appending n$nestCnt");
    $v .= ".n$nestCnt";
    $r .= ".n$nestCnt";
    $q[0]('nestCalls#' . ++$nestCnt);
    outLi("nest($a)", ++$nestCnt, "v=$v, r=$r, appending n$nestCnt");
    $v .= ".n$nestCnt";
    $r .= ".n$nestCnt";
    $q[1]('nestCalls#' . ++$nestCnt);
    outLi("nest($a)", ++$nestCnt, "v=$v, r=$r");
    return $q;
}



outH('church numerals');
outTB();
tr("?", function($l, $r) {return "$l ? $r"; }, 'outTH');

function p1($x) { return ++$x; }
function n0 ($f, $z) { return $z; }
function n1 ($f, $z) { return $f($z); }
function n2 ($f, $z) { return $f($f($z)); }
$num = ['n0', 'n1', 'n2'
        , function ($f, $z) {return $f(n2($f,$z));} , function ($f, $z) {return $f($f(n2($f, $z)));} ];
tr("num[r]", function($l, $r) {global $num; return "$r -> " . call_user_func($num[$r], 'p1', 0);});

function scc($a) { return function($f, $x) use ($a) {return $f($a($f, $x)); } ; }
function add($l, $r) { return function($f, $x) use ($l, $r) {return $l($f, $r($f, $x)); } ; }
function mult($l, $r) { return function($f, $x) use ($l, $r) {return $l(
                    function($y) use ($l, $r, $f) { return $r($f, $y); }
                    , $x); } ; }
function mulA($l, $r) { return function($f, $x) use($l, $r) { return $r(aL($l), 'n0')($f, $x); } ; }
function powr($l, $r) { return function($f, $x) use($l, $r) { return $r(
                    function($v) use($l) { return mult($l, $v);}, 'n1')($f, $x); } ; } 
function powM($l,  $r) { return function($f, $x) use($l, $r) { return $r(mL($l), 'n1')($f, $x); } ; }

tr("scc(r)", function($l, $r) {global $num; return "$r -> " . scc($num[$r])('p1', 0);});
outTCF('l', 'r');
tr("add(l, r)", function($l, $r) {global $num; return add($num[$l], $num[$r])('p1', 0);});
tr("mult(l, r)", function($l, $r) {global $num; return mult($num[$l], $num[$r])('p1', 0);});
tr("mulA(l, r)", function($l, $r) {global $num; return mulA($num[$l], $num[$r])('p1', 0);});
tr("powr(l, r)", function($l, $r) {global $num; return powr($num[$l], $num[$r])('p1', 0);});
tr("powM(l, r)", function($l, $r) {global $num; return powM($num[$l], $num[$r])('p1', 0);});
outTBEnd();
outEnd(__file__);

function aL($l) { return function($r) use($l) {return add($l, $r); } ; }
function mL($l) { return function($r) use($l) {return mult($l, $r); } ; }

function tr($h, $f, $td='outTD') {
    outTR();
    outTH($h);
    for ($l=0; $l <=3; $l++) 
        for ($r=0; $r <=4; $r++) 
            $td($f($l, $r));
}