def decrement(token: "Token", parser: "Parser") -> List[nodes.Node]:
"""The decrement tag {% decrement x %}
Args:
token: The token matches tag name
parser: The parser
Returns:
The parsed node
"""
variable = parser.stream.expect("name")
varname = f"_liquid_xcrement_{variable.value}"
varnode = nodes.Name(varname, "load")
return [
nodes.Assign(
nodes.Name(varname, "store"),
nodes.CondExpr(
nodes.Test(varnode, "defined", [], [], None, None),
nodes.Sub(varnode, nodes.Const(1)),
nodes.Const(-1),
),
lineno=token.lineno,
),
nodes.Output([varnode], lineno=token.lineno),
]
def parse_sub(self):
lineno = self.stream.current.lineno
left = self.parse_concat()
while self.stream.current.type == 'sub':
next(self.stream)
right = self.parse_concat()
left = nodes.Sub(left, right, lineno=lineno)
lineno = self.stream.current.lineno
return left
