String _ Sequence -- substring

Synopsis

• Operator: _
• Usage:
s_(i,j)
• Inputs:
• s,
• (i,j), a pair of integers
• Outputs:
• , the substring of s having length j and starting at the i-th character

Description

 i1 : s = "I did not do that!" o1 = I did not do that! i2 : "." | s_(6,7) | "." o2 = .not do .