The first step: marking
The first step in processing an expression is to convert it into a list of independent symbols. This is a simple step and not the focus of this article, so I've omitted a lot here.First, I've defined some tags (numbers are not in here, they are the default tags) and a tag type:
Token_map = {' + ': ' Add ', '-': ' Add ', ' * ': '
MUL ', '/': ' MUL ',
' (': ' LPAR ', ') ': ' Rpar '}
token = Namedtuple (' Token ', [' name ', ' value '])
Here is
0. PrefaceCommon current-limiting algorithms are: Token bucket, leaky bucket. The counter can also be used for rough current limit implementations.1. Algorithm Introduction 1.1 token bucket algorithmThe token bucket algorithm is a bucket that holds a fixed capacity token and adds a token to the bucket at a fixed rate. The token bucket algorithm is described as follows:
Assuming a limit of 2r/s, add a token to the bucket at a fixed rate of 500 milliseconds;
The bucket contains a maxi
and file parsing-Use File Parsing to process command output, strings, and file content. Use iteration variables to define the content or string to be checked, and use various options to further modify the resolution method. Use the options token option to specify which tokens should be passed as iteration variables.Note: When the token option is not used,/F checks only the first token. The file parsing process includes reading output, string, or file
Using 70 lines of Python code to implement a recursive descent parser tutorial, 70 lines of python
Step 1: Tagging
The first step in processing an expression is to convert it to a list containing independent symbols. This step is very simple and not the focus of this article, so I have omitted a lot here.First, I define some tags (numbers are not in this box, they are the default tags) and a tag type:
token_map = {'+':'ADD', '-':'ADD', '*':'MUL', '/':'MUL', '(':'LPAR', ')':'RPAR'} To
content or string to check, and further modify the resolution using various options choices. Use the Options token option to specify which tokens should be passed as iteration variables.Please note that if you do not use the token option,/F will only check the first token. The file resolution process involves reading the output, string, or file contents, dividing it into separate lines of text, and then parsing each row into 0 or more
displayed in the command shell, declare the key variables used for testing the automation program:string url = "https://localhost/LitwareOrder/Order.aspx";string viewstate = HttpUtility.UrlEncode( "dDw0MDIxOTUwNDQ7Oz6E/7ailqx8X9zCUfpbWTPybfS4MA==");string line;string[] tokens;StringBuilder data = new StringBuidler();byte[] buffer;string proxy = null;The purpose of most of the above variables is clear from its naming. Only viewstate is a new variab
the initial context of the matching (that is, DOM Element Set ). If the context value is not assigned, the document is used. * @ Param results: the final result of the matched part. If results is not assigned a value, an empty array is assigned. * @ Param seed initial set */function select (selector, context, results, seed) {var I, tokens, token, type, find, // call the tokenize function to parse selectormatch = tokenize (selector); // if the initial
selector removes the leading and trailing blank selector string * @ param context to execute the matched initial context (that is, the DOM Element Set ). If the context value is not assigned, the document is used. * @ Param results: the final result of the matched part. If results is not assigned a value, an empty array is assigned. * @ Param seed initial set */function select (selector, context, results, seed) {var I, tokens, token, type, find, // c
I. OverviewFor command switches There are many,/l,/f,/r. This is only for analysis of the for with/F, which is probably the most commonly used and strongest command, mainly used to process the output of files and some commands.1. Command format:(1). for/f ["Options"]%%i in (file) do command(2). for/f ["Options"]%%i in ("string") do command--note double quotes(3). for/f ["Options"]%%i in (' command ') do command--Note single quotes2. Parameter Description:The file represents one or more files, an
concernAgreed access rate (CAR)Mode, that is:
A. Deliver the token to the token bucket at a specific rate;
B. Sort packets according to preset matching rules,Messages that do not comply with the matching rules do not need to be processed by the token bucket and sent directly;
C. For packets that comply with the matching rules, the token bucket must be processed. When the bucket has enough tokens, the message can be sent, and the amount of
scenario one in the three scenarios above that resulted in repeated submissions of forms, and for scene two and scene three, it is still not possible to resolve the form repeat submission Problem.third, use the session to prevent the form repeating the submissionFor "scene two" and "scene three" caused the form to repeat the problem, since the client cannot resolve, then the Server-side solution, the Server-side solution will need to use the Session.How to do this: generate a unique random iden
context to execute the initial context of the matching (that is, DOM Element Set ). If the context value is not assigned, the document is used. * @ Param results: the final result of the matched part. If results is not assigned a value, an empty array is assigned. * @ Param seed initial set */function select (selector, context, results, seed) {var I, tokens, token, type, find, // call the tokenize function to parse selectormatch = tokenize (selector)
following command:for/f%c in (d:\abc.txt) do @echo%cThe screen displays:NameTomJohn doeZhao Liu
Explanation: This is the case when the default parameter option is FOR/R before "% variable". Each round of the loop is delimited by a space, dividing the string by line in the open file, and because no additional variable (that is, only one variable%c) is added to the first paragraph assignments to%c, and then the Do command is executed. , and then loop the next round, and ignore blank lines by d
sequence, and then the command after do is executed.
Specific process:
Replace "1st rows, 1st columns, 1st rows, 2nd columns, 1st rows, and 3rd columns" with % I, show "1st rows, 1st columns, 1st rows, 2nd columns, 1st rows, 3rd columns ",
Replace "2nd rows, 1st columns, 2nd rows, 2nd columns, 2nd rows, 3rd columns" with % I, show "2nd rows, 1st columns, 2nd rows, 2nd columns, 2nd rows, 3rd columns ",
Until each element is replaced.
To enhance understanding of the role of/F, execute th
rows, 3rd columns ",
Until each element is replaced.
To enhance understanding of the role of/F, execute the following two commands for comparison:
For/F % I in (a.txt) Do echo % I // This will display the content in a.txt, because/F will read a.txt.
For % I in (a.txt) Do echo % I // This only displays the.txt name and does not read the content.
Through the above learning, we found that for/F will use each row as an element by default, but what if we want to break down each row into smaller cont
and does not read the content.
Through the above learning, we found that for/F will use each row as an element by default, but what if we want to break down each row into smaller content? Don't worry, the for command also provides us with more detailed parameters so that we can divide each row into smaller elements.
These are delims and tokens.
Delims is used to tell each line for what should be used as a separator. The default Delimiter is space and
provides us with more detailed parameters so that we can divide each row into smaller elements.
They are:Delims and tokens
Delims is used to tell for what should be used as a separator for each line,The default Delimiter is space and Tab key.
For example, if the above file is used, we can execute the following command:
For/F "delims =" % I in (a.txt) Do echo % I
The result is as follows:
1st rows and 1st Columns
2nd rows and 1st Co
Current item: Aergo
1. Aergo attempts to integrate public and private chains to better meet the needs of enterprise-class users. Most of the team technicians have experience in blockchain project development, but there are fewer people in charge of business development and market operation.
2. The project's "endorsement" Company Blocko has 4 years of experience in the blockchain industry, and its product coinstack has been commercially used. Aergo's core technology is based on Coinstack, and Blo
of the role of/F, execute the following two commands for comparison:
For/F % I in (a.txt) Do echo % I // This will display the content in a.txt, because/F will read a.txt.
For % I in (a.txt) Do echo % I // This only displays the.txt name and does not read the content.
Through the above learning, we found that for/F will use each row as an element by default, but what if we want to break down each row into smaller content? Don't worry, the for command also provides us with more detailed paramete
The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion;
products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the
content of the page makes you feel confusing, please write us an email, we will handle the problem
within 5 days after receiving your email.
If you find any instances of plagiarism from the community, please send an email to:
info-contact@alibabacloud.com
and provide relevant evidence. A staff member will contact you within 5 working days.