Skip to content

Latest commit

 

History

History
147 lines (118 loc) · 6.16 KB

README.md

File metadata and controls

147 lines (118 loc) · 6.16 KB
Raw

golang

Exercises from the book "The Go Programming Language"

Questions

  • X := 10 * time.Second

1. Tutorial

Program Purpose
a_helloworld the classic with unicode possible
b_echo1 echo with for i++ loop
c_echo2 echo with for range loop
d_echo3 echo with strings.Join
e_exercise-1.2 echo with index printed
f_exercise-1.3 Benchmark string concat vs join
g_dup1 check dup lines with bufio.NewScanner
h_dup2 bufio.NewScanner now takes *os.File args
i_dup3 read files at once with ioutil.ReadFile
j_exercise-1.4 dup with print filename from map[string]string
k_lissajous GIF animation with scifi sinus waves
l_fetch curl with a few lines
m_exercise-1.7 fetch using io.Copy to stdout
n_exercise-1.7b fetch auto adding http prefix to url
o_exercise-1.9 fetch printing http status code additionaly
p_fetchall fetch in parallel with goroutines
q_exercise-1.10 fetchall with writing contents to files
r_server1 web server doing simple echo
s_server2 web server with request count wieth Mutex
t_server3 web server printing headers and other http infos
u_server-gif web server sending GIF from k_lissajous

2. Program Structure

Program Purpose
a_retpointer returning a pointer to local var (escape analysis)
b_echo4 echo with flag.Parse()
c_cf celsius fahrenheit type conversion using package tempconv
d_bitlevel shift and mask on binary numbers
popcount counting number of bits set to 1 in a word
tempconv celsius fahrenheit type conversion package

3. Basic Data Types

Program Purpose
a_surface creating a SVG graphic with float calculations
b_exercise-3.3 adding color gradient from red to blue
c_surfserver serving svg via http server

4. Composite Types

Program Purpose
a_sha256 printf sha256 sums of type [32]byte with %x
b_exercise-4.1 counting the bits set diffently in two sha256 sums
c_exercise-4.2 reading all STDIN and printing the sha256 sum of it
d_rev reverse a slice
e_exercise-4.3 reverse array [6]int
f_exercise-4.4 left rotate a slice
g_exercise-4.5 remove adjacent duplicates from string slice
h_exercise-4.6 in place squash unicode spaces into ascii space
i_charcount charcount NewReader(STDIN) ReadRune()
j_charclass count character classes
k_wordfreq count word frequencies with NewScanner / Split ScanWords
l_github github json api client with structs
m_issues command line issue search for github
n_exercise-4.10 classify github issues search results by age new or old
o_exercise-4.13 command line client for movie poster download
p_issuesreport issue rendering with text template
q_issueshtml issue rendering with html template
r_exercise-4.14 web server rendering html issue info

5. Functions

Program Purpose
a_findlinks parse html (stdin) and find links
b_exercise-5.1 findlinks without for loop
c_exercise-5.2 count types of element nodes in map
d_exercise-5.3 parse html TextNodes and print to stdout
e_exercise-5.4 findlinks1 + additionally find other links like images and scripts
f_outline2 print outline of a parsed html tree from url
g_exercise-5.7 pretty printing the parsed html
h_exercise-5.8 implemented getElementById on parsed html tree
i_exercise-5.9 expanding $foo with function argument

6. Methods

Program Purpose
a_intset set of small integers implemented as Bit Vector
b_exercise-6.1 added some methods
c_exercise-6.2 added variadic AddAll Method
d_exercise-6.3 added Intersect and Difference Methods
e_exercise-6.4 added Elems Method returning slice for range loop

7. Interfaces

Program Purpose
a_exercise-7.1 LineCounter and WordCounter implementing the Writer interface
b_exercise-7.2 CountingWriter returns a Wrapper to a given io.Writer + *counter
c_exercise-7.3 added String Method to tree type
d_exercise-7.4 reimplement strings.NewReader
f_tempflag tempconv command line - celsiusFlag satisfies flag.Value interface
g_exercise-7.9 html table using sort.Interface
h_exercise-7.11 update func adapted to http.Handler interface using DefaultServeMux
i_eval expression evaluator
j_exercise-7.13 add String method to Expr interface
k_xmlselect print the text of xml elements selected py path
l_exercise-7.17 xmlselect also by attributes
m_exercise-7.18 constructing a tree of generic nodes from xml tokens

8. Goroutines and Channels

Program Purpose
a_exercise-8.1 clock server and clients with goroutines
b_exercise-8.2 FTP Server
c_exercise-8.3 netcat3 -> *net.TCPConn.CloseWrite()
d_exercise-8.4 using sync.WaitGroup to count the number of active echo goroutines
e_exercise-8.8 echoserver now has timeout using select statement
f_exercise-8.9 du status updates now seperate for each root
g_chatserver a server broadcasting chat messages to all tcp clients like netcat
h_exercise-8.12 announce set of clients to new arrivals
i_exercise-8.13 added timeout to chat server
j_exercise-8.14 chat servers network protocol now asks for user name

9. Concurrency With Shared Variables

Program Purpose
a_exercise-9.1 withdraw added to bank1
b_exercise-9.5 found limit of ~ 2.5 mio goroutines with 8GB Memory
c_exercise-9.6 found limit of ~ 4.5 mio messages per second