expand build_path docstring for path_patterns arg
@@ -868,7 +868,17 @@ class BIDSLayout(object):
values
path_patterns (list): Optional path patterns to use to construct
the new file path. If None, the Layout-defined patterns will
- be used.
+ be used. Entities should be represented by the name
+ surrounded by curly braces. Optional portions of the patterns
+ should be denoted by square brackets. Entities that require a
+ specific value for the pattern to match can pass them inside
+ carets. Default values can be assigned by specifying a string
+ after the pipe operator. E.g., (e.g., {type<image>|bold} would
+ only match the pattern if the entity 'type' was passed and its
+ value is "image", otherwise the default value "bold" will be
+ used).
+ Example: 'sub-{subject}/[var-{name}/]{id}.csv'
+ Result: 'sub-01/var-SES/1045.csv'
strict (bool): If True, all entities must be matched inside a
pattern in order to be a valid match. If False, extra entities
will be ignored so long as all mandatory entities are found.
