The "hedge" referred to iron bars, and in later generations, going to jail was colloquially known as sitting behind the hedge, which referred to the iron bars welded to the prison windows. Wang Yunxiao wasn't too clear on whether modern prisons had such conditions, but if you just mentioned "hedge," that meant a long-bladed weapon.
The local customs of Tianmen stated that weapons should not be seen on the streets, and even if the townsfolk had huge grievances with each other, they weren't allowed to wield knives openly in broad daylight on the streets.
But, as the saying goes, rules are made to bind the honest. The gangs of the local Jianghu World might talk about rules among themselves, but as for the outsiders who crossed the river, who cared about your rules?
Little Gourd's words meant that someone outside was fighting, using real weapons.
Wang Yunxiao was so furious he gritted his teeth, wondering which bastard from which path had specially come to give him trouble today.