Add tasks for all the new languages

Task/Topological-sort/EchoLisp/topological-sort-1.echolisp

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+(define dependencies
+'((des_system_lib   std synopsys std_cell_lib des_system_lib dw02 dw01 ramlib ieee)
+(dw01             ieee dw01 dware gtech) ;; bad graph add dw04
+(dw02             ieee dw02 dware )
+(dw03             std synopsys dware dw03 dw02 dw01 ieee gtech)
+(dw04             dw04 ieee dw01 dware gtech)
+(dw05             dw05 ieee dware)
+(dw06             dw06 ieee dware)
+(dw07             ieee dware)
+(dware            ieee dware)
+(gtech            ieee gtech)
+(ramlib           std ieee )
+(std_cell_lib     ieee std_cell_lib)
+(synopsys         )))
+
+
+;; build dependency graph
+;;  a depends on b
+;;  add arc (arrow) a --> b
+(lib 'graph.lib)
+(define (a->b  g a b)
+		(unless (equal? a b)
+		(graph-make-arc g (graph-make-vertex g a) (graph-make-vertex g b))))
+
+(define (add-dependencies g dep-list)
+(for* ((dep dep-list)  (b (rest dep))) (a->b  g b (first dep))))

Task/Topological-sort/EchoLisp/topological-sort-2.echolisp

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+;; topological sort
+;;
+;; Complexity O (# of vertices + # of edges)
+
+(define (t-sort g)
+	(stack 'Z) ; vertices of d°(0)
+	(stack 'S) ; ordered result
+
+;; mark all vertices with their in-degree = # of incoming arcs
+;; push all vertices u such as d°(u) = 0
+	(for ((u g)) (mark u (graph-vertex-indegree g u))
+	             (when (zero? (mark? u)) (push 'Z u)))
+	
+;pop a d°(0) vertex u - add it to result
+;decrement in-degree of all v vertices u->v
+; if d°(v) = 0, push it
+
+(while (not (stack-empty? 'Z))
+  			(let  (( u (pop 'Z)))
+ 			(push 'S u)
+			 (for ((v (graph-vertex-out g u)))
+				  (mark v (1- (mark? v)))
+				  (when (zero? (mark? v)) (push 'Z v)))))
+				
+;; finish
+		 (writeln 't-sort (map vertex-label (stack->list 'S)))
+		
+;; check no one remaining
+		(for ((u g))
+		(unless (zero? (mark? u))
+		(error " ♻️ t-sort:cyclic" (map vertex-label (graph-cycle g))))))

Task/Topological-sort/EchoLisp/topological-sort-3.echolisp

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+(define g (make-graph "VHDL"))
+(add-dependencies g dependencies)
+(graph-print g)
+
+(t-sort g)
+→ t-sort     (std synopsys ieee dware dw02 dw05 dw06 dw07 gtech dw01 dw03 dw04 ramlib
+             std_cell_lib des_system_lib)
+
+;; Error case
+;; add dw01 -> dw04
+(t-sort g)
+t-sort     (std synopsys ieee dware dw02 dw05 dw06 dw07 gtech ramlib std_cell_lib)
+⛔️ error: ♻️ t-sort:cyclic (dw04 dw01)