Does anybody know what "<space>" means for line-height???Know? I guess not. But judging from the spec...
Ah well, I overlooked this....
"XSL adds the following value with the following meaning: <space> Specifies the minimum, optimum, and maximum values, the conditionality and precedence of the 'line-height' that is used in determining the half-leading."
Perhaps this is just a way of saying that 'line-height' can be 'shorthanded'
line-height="min opt max cond prec"??
Uh no, it's more ugly: line-height is actually meant to be a "compound" property, like space-before. I.e. it is possible to write <fo:block line-height.optimum="12.5pt" line-heigth.maximum="13pt" ... The precedence and conditionality are combination of the half-leading with space-before and space-after at the beginning and the end of the block, I think.
I see why they thought this is necessary, but this kind of spec makes it unnecessary hard to follow.