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"{{T defined|a|a=3}}" gives "{{{{{subst}}}#ifeq: +|-|1|0}}" [1]"{{T defined|a|b=3}}" gives "{{{{{subst}}}#ifeq: +|-|1|0}}" [2]"{{T defined|a|b=3|a=4}}" gives "{{{{{subst}}}#ifeq: +|-|1|0}}" [3]"{{T defined|2|3|4}}" gives "{{{{{subst}}}#ifeq: 3|3|1|0}}" [4]
