Just quickly wrote this little thingy for debugging ‘unexpected EOF’ errors in Go standard templates.

checktpltags.py

import os, sys

if len(sys.argv) > 1:
	exp = open(sys.argv[1]).read()
else:
	exp = raw_input("Write template (or try again with file path as argument): ")
	for l in os.sys.stdin:
		exp += l

print
print
print

tags = ['with', 'range', 'if']
stack = []
line = 1
col = 0
def print_op(op, line, col, i):
	if op:
		print op+":",
	print "%s:%s" % (line, col),
	j = i
	while exp[j:j+2] != "}}":
		j += 1
	print exp[i:j+2]

def print_stack():
	print "<<<"
	for p in stack:
		print_op(None, p[1], p[2], p[0])
	print ">>>"
	print

for i in range(len(exp)):
	col += 1
	for tag in tags:
		if exp[i:i+len('{{'+tag)] == '{{'+tag:
			stack.append((i, line, col))
			print_op("Open", line, col, i)
			print_stack()
	if exp[i] == '\n':
		line += 1
		col = 0
	elif exp[i:i+len('{{end')] == '{{end':
		p = stack.pop()
		print_op("Close at %s:%s" % (line, col), p[1], p[2], p[0])
		print_stack()

if len(stack) != 0:
	p = stack.pop()
	print "UNCLOSED line", "%s:%s" % (p[1], p[2]),":", exp[p[0]:p[0]+20]
else:
	print "OK"