Question: Perl provides an alternative (?:. . . ) form of parentheses that supports grouping in regular expressions without performing capture. Using this syntax, Example 14.57

Perl provides an alternative (?:. . . ) form of parentheses that supports grouping in regular expressions without performing capture. Using this syntax, Example 14.57 could have been written as follows:

$if (/^([+-]?) ((\d+)\.I(\d*)\. (\d+))(?:e([+-]?\d+))?$/) { # floating-point number print$ What purpose does this extra notation serve? Why might the code here be preferable to that of Example 14.57?

if (/^([+-]?) ((\d+)\.I(\d*)\. (\d+))(?:e([+-]?\d+))?$/) { # floating-point number print "sign: print "integer: ", $3, $4, " "; print "fraction: print "mantissa: " print "exponent: ", $6, " "; ", $1, " "; $5, " "; $2, " "; # not $7 %3D

Step by Step Solution

★★★★★

3.44 Rating (154 Votes )

There are 3 Steps involved in it

1 Expert Approved Answer

Step: 1 Unlock

Capturing subexpressions takes time In an inner loop the cost of unneces... View full answer

Question Has Been Solved by an Expert!

Get step-by-step solutions from verified subject matter experts

Step: 2 Unlock

Step: 3 Unlock

Students Have Also Explored These Related Programming Language Pragmatics Questions!

An alternative form of the S-R latch has the same structure as Figure 20.22 but uses NAND gates instead of NOR gates. a. Redo Table 20.10a and 20.10b for S-R latch implemented with NAND gates. b....

An alternative form of estimation is accomplished through the method of moments. The method involves equating the population mean and variance to the corresponding sample mean x and sample variance s...

As an alternative alphanumeric code, consider a code where punched holes in the columns of a card represent alphanumeric codes. The punched hole represents a 1; all other bits are 0. The Hollerith...

Please read the question Question : What strategies have you used to communicate in a language you were acquiring? What strategies do you think emergent bilinguals use? 3 How Do People Learn and How...

INTERNATIONAL REVIEW OF L AW C OMPUTERS & TECHNOLOGY , VOLUME 11, N UMBER 2, P AGES 251-261, 1997 The Data Mart: A New Approach to Data Warehousing PAM ELA PIPE Introduction Vendors have recently...

ttth Suppose that the sequence of bags {Bn | n N} is recursively enumerated by the computable function e(n, x) = fn(x), [7 marks] Hence prove that the set of all recursive bags cannot be recursively...

can someone solve this Modern workstations typically have memory systems that incorporate two or three levels of caching. Explain why they are designed like this. [4 marks] In order to investigate...

MATHEMATICS FOR MACHINE LEARNING Marc Peter Deisenroth A. Aldo Faisal Cheng Soon Ong Contents Foreword 1 Part I Mathematical Foundations 9 1 Introduction and Motivation 11 1.1 Finding Words for...

Data gistrun sending inside a pack fills in as conventional allowing subordinate rules to execute on progressive clock cycles. Correspondence between gatherings conventionally causes a surprising...

Please read the question Question: Give five examples (one per hypothesis) of actions teachers can take to support a child's second language development using the five hypotheses in Krashen's Monitor...

On March 31, 2024, Chow Brothers, Incorporated, bought 10% of KT Manufacturing's capital stock for $50 million, KT's net income for the year ended December 31, 2024, was $80 million. The fair value...

In the survey of Exercise 17.18, the clerical employees in the eight sampled subdivisions were asked if they were satisfied with the operation of the bonus plan. The results obtained are listed in...

range of f ^ - 1 ( x ) = square root of ( y + 6 )

4. Discuss the attitude of the following cultures to the practice of giving gifts as mementos: (a) Indians (b) Japanese (c) Germans (d) Americans

A signal with 200 milliwatts power passes through 10 devices, each with an average noise of 2 microwatts. What is the SNR? What is the SNRdB?

A computer monitor has a resolution of 1200 by 1000 pixels. If each pixel uses 1024 colors, how many bits are needed to send the complete contents of a screen?

A file contains 2 million bytes. How long does it take to download this file using a 56-Kbps channel? 1-Mbps channel?

Which of the following is true about exclusively federal area of government regulation? A. It concerns those internal matters where uniformity on a nationwide basis is essential. B. In this area,...

Last year Clark Company issued a 10-Year, 12.5% semiannual Coupon Bond at its Par Value of $1,000. Currently the Bond can be called in four (4) years at a price of $1,065 and it sells for $1,105....

16. High Point Hotel (HPH) has $165,000 in accounts receivable. To finance a major purchase, the company assigns these receivables to Cross Town Bank. Which one of the following statements correctly...