Calculation engine was resolving every function by first resolving its arguments
including IFs, this was causing significant over evaluation when IFs were used
as it meant for every case to be evaluated.
Introduce elements to identify ifs and enable better branch resolution
(pruning). We tag parsed tokens to associate a branch identifier to them.
Closes#844
Commit 8dddf56 inadvertently removed the ability to omit the width
and height arguments to the OFFSET function. And #REF! is returned
because the function is validating that the new $pCell argument
is present. It is present, but it has been passed in the $height position.
We fixed this by always passing $pCell at the last position and filling
missing arguments with NULL values.
Fixes#561Fixes#565
This change adds support for newer functions that are prefixed
by _xlfn. (#356). The calculation engine has been updated to
recognise these as functions, and drop the _xlfn. part.
It also add a couple of the new functions such as STDEV.S/P,
MODE.SNGL, ISFORMULA.
Fixes#356Closes#390
yunjusu