cessante ratione legis cessat ipsa lex
The maxim says a rule depends on its reason: when the reason disappears, the rule should not be applied. It works best for judge-made rules and for deciding whether a rule extends to a situation its reason does not reach.
In India it does not let a court treat a statute as repealed. An enacted law stays in force until the legislature repeals it or a court strikes it down. What courts have done is hold that a classification which was reasonable when made may become arbitrary with changed conditions, and so violate Article 14. Old rent control laws have been tested this way. Use the maxim as an argument about reasons, not as a ground of invalidity by itself.
Example
Applying cessante ratione legis cessat ipsa lex, counsel argued that a rent freeze justified by post-war scarcity had become arbitrary once that scarcity ended.