Tricky ones

Warning: These are all truthy.

  • Null number. 
      my_int: 0
  • Null string. 
      my_string: ''
  • Null array. 
      my_array: []
  • Null hash; 
      my_hash: {}

If you come from a Python background these are all unexpected.

For a JavaScript programmer, you would be used to an empty object [] being truthy but you’re would expect to find an empty string or number falsy, but not in Jekyll.

Easy ones

These are the obvious values that are truthy.

---
my_int: 123

my_str: '123'

my_array: [ 123 ]
# OR
my_array:
  - 123

my_hash: { 'a': 1 }
# OR
my_hash:
  a: 1

my_bool: true
---