@Override
	public void supprimerArriere() {
		if(this.selection.getLongueur() > 0) {
			this.buffer.effacer(this.selection.getDebut(), this.selection.getFin());
			this.selection.setFin(this.selection.getDebut());
		} else if(this.selection.getDebut() > 0) {
			this.buffer.effacer(this.selection.getDebut()-1,this.selection.getDebut());
			this.selection.setDebut(this.selection.getDebut()-1);
			this.selection.setFin(this.selection.getDebut());
		}
		this.setChanged();
		this.notifyObservers(this.buffer.getContenu());
		this.setChanged();
		this.notifyObservers(this.selection.getDebut());
	}