#!/usr/bin/env python2 import sys with open("../fontMetrics.js", "r") as metrics: old_lines = file.readlines(metrics) replace = sys.stdin.read() with open("../fontMetrics.js", "w") as output: for line in old_lines: if line.startswith("var metricMap"): output.write("var metricMap = ") output.write(replace) output.write(";\n") else: output.write(line)