Module interpolation

Parse the given string and extract expressions.

This function is a generator that yields TEXT events for literal strings, and EXPR events for expressions, depending on the results of parsing the string.

>>> for kind, data, pos in interpolate("hey ${foo}bar"):
...     print('%s %r' % (kind, data))
TEXT 'hey '
EXPR Expression('foo')
TEXT 'bar'

Parameters:

• text - the text to parse
• filepath - absolute path to the file in which the text was found (optional)
• lineno - the line number at which the text was found (optional)
• offset - the column number at which the text starts in the source (optional)
• lookup - the variable lookup mechanism; either "lenient" (the default), "strict", or a custom lookup class

Returns:

a list of TEXT and EXPR events

Raises:

• TemplateSyntaxError - when a syntax error in an expression is encountered