A simple snippet that allows you to compile a Crunch expression that uses PlaceholderAPI placeholders.

PlaceholderExpression.java

package redempt.test;

import me.clip.placeholderapi.PlaceholderAPIPlugin;
import me.clip.placeholderapi.expansion.PlaceholderExpansion;
import me.clip.placeholderapi.expansion.manager.LocalExpansionManager;
import org.bukkit.entity.Player;
import redempt.crunch.CompiledExpression;
import redempt.crunch.Crunch;
import redempt.crunch.data.FastNumberParsing;
import redempt.crunch.functional.EvaluationEnvironment;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class PlaceholderExpression {
	
	private static Pattern placeholderPattern = Pattern.compile("%([^% ]+)_([^% ]+)%");
	
	private CompiledExpression exp;
	private Player player;
	
	public PlaceholderExpression(String str, EvaluationEnvironment env) {
		Matcher matcher = placeholderPattern.matcher(str);
		LocalExpansionManager manager = PlaceholderAPIPlugin.getInstance().getLocalExpansionManager();
		while (matcher.find()) {
			String placeholder = matcher.group();
			String identifier = matcher.group(1);
			String arg = matcher.group(2);
			PlaceholderExpansion expansion = manager.getExpansion(identifier);
			if (expansion == null) {
				continue;
			}
			env.addLazyVariable(placeholder, () -> {
				String replaced = expansion.onRequest(player, arg);
				if (replaced == null) {
					return 0;
				}
				return FastNumberParsing.parseDouble(replaced);
			});
		}
		exp = Crunch.compileExpression(str, env);
	}
	
	public PlaceholderExpression(String str) {
		this(str, new EvaluationEnvironment());
	}
	
	public double evaluate(Player player) {
		this.player = player;
		return exp.evaluate();
	}
	
}