@replace(t:tab, find:value, rep:value)
returns a new tab in which a number of elements have been replaced by another.

The argument find represents a sub-sequence to be replaced: if it is not a tab, then all the occurrences of this value at the top-level of t are replaced by rep: 

       $t := [1, 2, 3, [2]]
       @replace($t, 2, 0) -> [1, 0, 3, [2]]
If find is a tab, then the replacement is done on sub-sequence of t: 
       @replace([1, 2, 3, 1, 2], [1, 2], 0) -> [0, 3, 0]
Note that the replacement is done eagerly: the first occurrence found is replaced and the replacement continue on the rest of the tab. Thus, there is no ambiguity in case of overlapping sub-sequences, only the first is replaced: 
       @replace([1, 1, 1, 2], [1, 1], 0) -> [0, 1, 2]
If the argument `rep is a tab, then it represents at sub-sequence to be inserted in place of the occurrences of find. So, if the replacement is a tab, it must be wrapped into a tab: 
       @replace([1, 2, 3], 2, [4, 5]) -> [1, 4, 5, 3]
       @replace([1, 2, 3], 2, [[4, 5]]) -> [1, [4, 5], 3]

See also Tab Manipulations @binary_search    @car    @cdr    @clear    [@clone]    @concat    @cons    @copy    @count    @dim    @domain    @drop    @empty    @find    @flatten    @gnuplot    @insert    @iota    @is_list    @is_prefix    @is_subsequence    @is_suffix    @lace    @last    @listify    @map    @max_val    @median    @member    @normalize    @occurs    @parse    @permute    @push_back    @push_front    @range    @reduce    @remove    @remove_duplicate    @replace    @reshape    @resize    @reverse    @rotate    @scan    @scramble    @size    @slice    @sort    @sputter    @stutter    @succession    @tab_history    @tab_history_date    @tab_history_rdate    @take    @to_num