# chickadee » srfi-127 » lseq=?

##### Identifier search
lseq=? elt=? lseq1 lseq2procedure

Determines lseq equality, given an element-equality procedure. Two lseqs are equal if they are of the same length, and their corresponding elements are equal, as determined by elt=?. When elt=? is called, its first argument is always from lseq1 and its second argument is from lseq2.

The dynamic order in which the elt=? procedure is applied to pairs of elements is not specified.

The elt=? procedure must be consistent with eq?. This implies that two lseqs which are eq? are always lseq=?, as well; implementations may exploit this fact to "short-cut" the element-by-element equality tests.