ClickHouse/src/Interpreters/RewriteAnyFunctionVisitor.h

#pragma once

#include <unordered_set>

#include <Parsers/IAST.h>
#include <Interpreters/InDepthNodeVisitor.h>

namespace DB
{

class ASTFunction;

/// Rewrite 'any' and 'anyLast' functions pushing them inside original function.
/// any(f(x, y, g(z))) -> f(any(x), any(y), g(any(z)))
class RewriteAnyFunctionMatcher
{
public:
    struct Data
    {
        std::unordered_set<IAST *> rewritten;
    };

    static void visit(ASTPtr & ast, Data & data);
    static void visit(const ASTFunction &, ASTPtr & ast, Data & data);
    static bool needChildVisit(const ASTPtr & node, const ASTPtr & child);
};
using RewriteAnyFunctionVisitor = InDepthNodeVisitor<RewriteAnyFunctionMatcher, false>;

}