code: function(techName, techPath, bundleNode, magicNode, cmd, decls, force) {
  
          var arch = this.ctx.arch,
              node = this.useFileOrBuild(new BemDeclNode.BemDeclNode({
                  root: this.root,
                  level: this.level,
                  item: this.item,
                  techPath: techPath,
                  techName: techName,
                  cmd: cmd,
                  decls: decls,
                  force: force
              }));
  
          if (!node) return;
  
          // Set bem create node to arch and add dependencies to it
          arch.setNode(node)
              .addChildren(node, node.getDependencies());
  
          bundleNode && arch.addParents(node, bundleNode);
          magicNode && arch.addChildren(node, magicNode);
  
          return node;
      }
docs: Creates BemDecl node which maps to 'bem decl [cmd] [decls]'.
  @param techName
  @param techPath
  @param bundleNode
  @param magicNode
  @param cmd Command to execute (merge or substract).
  @param decls Declaration paths to execute command on.
  @param [force]
  @return {Node | undefined}