Free Essay

Symbol Table

In: Computers and Technology

Submitted By vishzrules
Words 360
Pages 2
A symbol table is a data structure used by a language translator such as a compiler or interpreter, where each identifier in a program's source code is associated with information relating to its declaration or appearance in the source, such as its type, scope level and sometimes its location.

1 Uses

An object file will contain a symbol table of the identifiers it contains that are externally visible. During the linking of different object files, a linker will use these symbol tables to resolve any unresolved references.

A symbol table may only exist during the translation process, or it may be embedded in the output of that process for later exploitation, for example, during an interactive debugging session, or as a resource for formatting a diagnostic report during or after execution of a program.

2 Implementation

If a compiler is to handle a small amount of data, then the symbol table can be implemented as an unordered list, which is easy to code, but it is only suitable for small tables only. A symbol table can be implemented in one of the following ways:

• Linear (sorted or unsorted) list • Binary Search Tree • Hash table

3 Operations

A symbol table, either linear or hash, should provide the following operations.

insert()

This operation is more frequently used by analysis phase, i.e., the first half of the compiler where tokens are identified and names are stored in the table. This operation is used to add information in the symbol table about unique names occurring in the source code. The format or structure in which the names are stored depends upon the compiler in hand.

lookup()

lookup() operation is used to search a name in the symbol table to determine:

• if the symbol exists in the table. • if it is declared before it is being used. • if the name is used in the scope. • if the symbol is initialized. • if the symbol declared multiple times.

4 Scope Management

A compiler maintains two types of symbol tables: a global symbol table which can be accessed by all the procedures and scope symbol tables that are created for each scope in the program.

Similar Documents

Free Essay

How to Get Those Greek Letters and Math Symbols in Word and Html

...those Greek Letters and math symbols in Word and html One of the irritations of math online are the symbols. You will need to insert math symbols and Greek letters into your documents whether you are using html, Word or Excel to communicate your results. The Character Map. One way to find the symbols you need is by a Windows accessory Character Map: For my computer ... Click Start (the button you use to turn off your computer), click Programs, click Accessories, click Systems Tools, click Character Map. Once the Character Map is displayed on your desktop, select the Symbol font from the font menu and use the select and copy functions to copy symbols to the Windows clipboard. Alternatively! The alternative is to select the symbol you wish from the table below, then follow the directions. Alt refers to the key left of the spacebar on your keybord.If you have the Number Lock activated on your keyboard (press the key Num Lock), it is easiest to type the digit combinations using the numerical key pad on the right of the keyboard. For Word / Excel For html symbol for Word / Excel  Select Symbol font then keystrokes alt + 0163  Select Symbol font then keystrokes alt + 0179  Select Symbol font then keystrokes alt + 0185  Select Symbol font then keystrokes alt + 0214  Select Symbol font then keystrokes alt + 0184 ² keystrokes alt + 0178 (no font change necessary) ³ keystrokes alt + 0179 (no font change necessary)  Select Symbol font then m on your keyboard ...

Words: 339 - Pages: 2

Free Essay

Hills Like White Elephants

...the theme is overcoming challenges during major life decisions and the importance of communication and courage during a time of crisis. A few of the symbols in the story were hills, white elephants, and a railroad. This was a story of a couple’s struggle with a life changing decision to have or abort a baby. As they both sat at a train station, they discussed the American’s desire for an abortion and Jig’s want for the pregnancy. She gazed in the distance at the hills on one half of the valley, which were dry, hot, and lifeless. “The girl was looking off at the line of hills. They were white in the sun and the country was brown and dry.” I feel this may have symbolized the couple’s challenges, Jig’s fear of her dead baby, being barren and the American’s desire for their lives to remain the same, stationary, and permanent (or the permanence of a baby). The hills on that side of the valley were compared to white elephants. White elephants are an ironic symbol of an awkward topic needing to be discussed and/or a useless gift. In the white elephant game, a gift is given as a joke and may be of no use to the recipient. As the American and Jig continue to discuss their wishes with the pregnancy, Jig sees the other side of the valley and it’s hills. They are described as alive, growing, and full of life. I feel this is a symbol of Jig seeing this crisis as an opportunity, life, growth, and a renewal for what seems like an unsatisfying relationship. “And we could have all this...

Words: 501 - Pages: 3

Free Essay

Hills Like White Elephants

...settings , Hemingway depicts psychological and emotional state of the characters . The main setting is a bar by a train station It is possible to assume that the train station symbolizes future changes in lives of both heroes . The American and the girl with him sat at a table in the shade , outside the building (Hemingway Dark ' colors usually means evil , loosing hopes and disappointment and more important life and death . Hemingway depicts this situation metaphorically : the American and the girl are sitting in the shade trying to find the right decision to their problem . Following David Wyche interpretation , The station is situated between two sets of rails , whose significance lies "in their figurative implications (Renner 34 cited Wyche , and between two contrasting landscapes that symbolize the couple 's options (Wyche , 2002 , . 56 . It is associated with one or another of the main thought-feelings of the story : abortion verses a new life To some extent , the use of settings reflects inner state of the characters and moral dilemma they are faced with . They sat down at the table and the girl looked across at the hills on the dry side of the valley and the man looked at her and at the table (Hemingway . This underlines the physiological state of common people affected by the crisis who are sick and tied of instability . Using settings of hills , the author...

Words: 498 - Pages: 2

Free Essay

Symbols

...Home Page » English and Literature The Welcome Table In: English and Literature The Welcome Table I read “The Welcome Table by Alice Walker. The Welcome Table is told in the third person and shifts the point of view from which the story is told. The theme of this story is a simple, but good one. The theme of this is about an old, rundown black woman who staggers the necessary distance in the freezing cold to attend an all-white people church. What captured my interest about this short story is the religious symbolism. Per R. Wayne Clugston “a symbol is an object, person, or action that conveys two meaning: its own literal meaning and something it stands for as well” (Clugston, 2010, p.480). It is filled with symbolism of life and death; good and evil; love and hatred; and peace and anger. Throughout this paper, Alice will demonstrate the significance of how the application of point of view, setting, and symbolism plays a role contributing the theme of a story. In the story, a black woman enters a “white” church. She is a woman of faith; “there was a dazed and sleepy look in her aged blue–brown eyes” (Clugston, 2010) blue symbolizes a peacefulness that this woman has because of her faith. She is not a welcomed visitor to this congregation, though. The parishioners feel “a fear of the black and the old” (Clugston, 2010), the use of the word black is not just to tell us the color of her skin, but to symbolize evil. This is further supported in the words...

Words: 373 - Pages: 2

Premium Essay

The Welcome Table

...I read “The Welcome Table by Alice Walker. The Welcome Table is told in the third person and shifts the point of view from which the story is told. The theme of this story is a simple, but good one. The theme of this is about an old, rundown black woman who staggers the necessary distance in the freezing cold to attend an all-white people church. What captured my interest about this short story is the religious symbolism. Per R. Wayne Clugston “a symbol is an object, person, or action that conveys two meaning: its own literal meaning and something it stands for as well” (Clugston, 2010, p.480). It is filled with symbolism of life and death; good and evil; love and hatred; and peace and anger. Throughout this paper, Alice will demonstrate the significance of how the application of point of view, setting, and symbolism plays a role contributing the theme of a story. In the story, a black woman enters a “white” church. She is a woman of faith; “there was a dazed and sleepy look in her aged blue–brown eyes” (Clugston, 2010) blue symbolizes a peacefulness that this woman has because of her faith. She is not a welcomed visitor to this congregation, though. The parishioners feel “a fear of the black and the old” (Clugston, 2010), the use of the word black is not just to tell us the color of her skin, but to symbolize evil. This is further supported in the words, “many of them saw jungle orgies in an evil place” (Clugston, 2010). The interesting thing about evil here is that...

Words: 545 - Pages: 3

Free Essay

Adsfmct

...for FREE Search Home Emoticons Smileys Symbols Facebook Symbols for Status Everyone fancy a cool status update decorated with facebook symbols. People always wonder how their friends got symbols for status when they add hearts, music notes , stars and other signs into their status. Actually its not difficult. Follow my steps and you will learn how to add facebook symbols for status. Before you start decoration your status updates with symbols, take a look at complete list of all facebook symbols. These are Unicode text characters that you can put into your status. Just use your imagination and creativity and you will come up with nice ideas. Take these symbols and combine them to create status decoration where you can add your ‘text update’. Most common facebook symbols people use for decoration are heart symbol, star symbol, math signs and music notes. Here we have got the most comprehensive list of facebook status symbols. Just copy and paste them in your status. ๑۩۞۩๑ Type your status message!! ๑۩۞۩๑ ๑۩๑ Type your status message!! ๑۩๑ ▂ ▃ ▅ ▆ █ Type your status message █ ▆ ▅ ▃ ▂ ★·.·´¯`·.·★ facebook symbols for status ★·.·´¯`·.·★ ..♩.¸¸♬´¯`♬.¸¸¤ Type your status message here o ¤¸¸.♬´¯`♬¸¸.♩.. ¤♥¤Oº°‘¨☜♥☞¤ symbols for facebook status ¤☜♥☞¨‘°ºO¤♥¤ ♬ •♩ ·.·´¯`·.·♭•♪ This is musical notes ♪ •♭·.·´¯`·.·♩ •♬ »——(¯` Type your status message here ´¯)——» ¸.·’★¸.·’★*·~-.¸-(★ facebook symbols ★)-,.-~*¸.·’★¸.·’★ •(♥).•*´¨`*•♥•(★) Type...

Words: 579 - Pages: 3

Premium Essay

Symbolism In Shirley Jackson's The Lottery

...her purpose of writing by stating her it as, “to shock the story’s readers with a graphic demonstration of the pointless violence and general inhumanity in their own lives” (Backpack p. 236). That quote alone is shown throughout “The Lottery” because there is most definitely a shock factor at the end of the story. A reader almost must read it twice to fully comprehend all that goes on in the town square of Jacksons’ story. However, as one reads “The Lottery”, one can identify many comparisons using symbolism and when one reads the story again, one can identify even more symbols. In Shirley Jacksons’ short story, “The Lottery”, there are many different items in the book like names, a three-legged table, a black box, and stones to show symbolism and allegory throughout the story. Jackson places her symbols in a specific order and it is that order in which the symbols have the most impact. The first symbol that comes along in the story is Mr. Summers. Mr. Summers is described as, “a...

Words: 1428 - Pages: 6

Premium Essay

Theme and Narrative Elements in Hills Like White Elephants

...Theme and Narrative Elements in Hills like White Elephants Lila Wright ENG 125 Kendall Shearman October 2, 2014 Theme and Narrative Elements in Hills like White Elephants In the short story Hills like White Elephants, symbols are other narrative elements are used to illuminate the theme by stirring feelings in the reader, heightening the conflict, or creating a certain mood while reading the story. Theme in a story is a representation of the idea behind the story (Clugston, 2014). In Hills like White Elephants the theme of meaningless is contributed to many literary elements, in which setting, symbols, and characters will be discussed in this paper. In Hills like White Elephants, the story is primarily a conversation between an American man and a girl nicknamed Jig. The rift between the two characters is shown by the way the course of the conversation, in which it is merely just talking because neither of the characters is truly communicating with the other. Both the American man and the girl are talking but not listening to the other’s point of view. Although it is not mentioned by name, the operation they speak of is an abortion. The American man is frustrated and tries to convince the girl, his girlfriend, to have the operation anyway he can. He tells her things will go back to the way they used to be if she has the abortion. The girl’s mind keeps changing and she ends up telling him at one point that she will do it just to get him to shut up. After he still persists...

Words: 1352 - Pages: 6

Premium Essay

Tobias Wolff's Hunters In The Snow

...habitual hunting trip. They almost hit him with their truck as they run halfway in the road and halfway on the sidewalk, and we see there is some immediate mistreatment between the group. As the story continues, there are many more instances where they encounter problems with each other. It is full of symbolism and imagery, and its sensitivity is shocking. A group of guys will wake up early in the morning, eat breakfast, put on camouflage, and spray themselves with pee to mask their own horrific scent. They will then go into a deer stand, sit there for hours, and watch the leaves move. This is an activity for guys, whether they are friends or father and son, to connect and work together as a team and complete a goal of putting food on the table. We do not see any of this in the story, however. In the story, the guys treat each other like a bunch of animals. While the other guys have slices of pizza and chocolate, Tub is eating a hard-boiled egg and a single stick of celery to mask the fact he is overweight because he eats so much when no one is looking. Kenny, another main character, responds with, “You’re wasting away before my very eyes”, and Frank, the third main character, says, “you haven’t seen your own balls in ten years” (162). These responses show how the guys do not care about how Tub feels, even though they do not understand his story and the struggles he goes through. Later in the story, Kenny decides he is fed up with the hunting trip and decides to shoot a post, a...

Words: 911 - Pages: 4

Premium Essay

The Stack

...The stack In life problems solved by confrontations is mandatory, no matter how hard you try to avoid them, sooner or later they will catch up, and stacking them instead of confronting them, will only make the problems bigger. Don’t wait for others to do your dishes take responsibility. That is among other things what Rose Tremain writes about in the short story ”The stack”, which was written and published in 2000. The story is told by an 3. Person omniscient narrator bound to John McCreedy. The main theme in the story is family problems that we can see, because the story is about a family that doesn’t function. The communication is bad, and the tone is hard between the members, they don’t like talking to each other and you get the feeling that the members in the family are alienated towards each other. The Story takes place in a small family in London it is in modern time, and about a modern family living in the suburban area. It can be seen through the language represented in the text: “Fuck off, Dad. Everyone remembers their fuckin’ age”. As shown in this quote. The main character is John McCreedy also known as McCreedy, he is father of 2 children and married to Hilda. Original McCreedy is from Ireland, which he misses enormously. He has a drinking problem and spends a little too much time in the pub: “But don’t go and spoil it by going out first and getting sloshed.” Through this quote it gets clear to us, that it is a regular thing for him to drink. We can assume...

Words: 988 - Pages: 4

Free Essay

Sorry for the Loss

...Sorry for the Loss * by Bridget Keehan The novel “Sorry for the Loss” by Bridget Keehan is about a woman called Evie who is prison chaplain. In the text she is about to tell an inmate that a relative of his died. This is the first time she is going to do this. The text is about the expectations she has towards telling him the grim news and how people can surprise you. She had her expectations and maybe even prejudices going into that cell. By analyzing symbols and reactions in the novel, this essay will look deeper on the reaction of the inmate Victor. This essay will also look at Evie’s workplace and how she feels about her work. Last, it will look at some of the symbols in the text and how they are used to make us understand certain points in the text. Victor reacts differently than Evie expected because he understand his situation. Victor seems to care very little about his grandmother’s death. At least compared to what you would expect but there is one thing you need to understand. Victor is in for murder and has done 5 years. He will be doing a lot more years and there is no point in becoming soft now. He knows the rules in the prison. “Is there anything you’d like me to do? I can find out the time of the funeral if you like?” “I won’t be able to go though will I, Miss?” (p. 4 l. 140-141). He would like to go if he could but he knows that he cannot so he does not want to seem like he cares. Prison is tough and when you are behind bars for as long as a man with...

Words: 986 - Pages: 4

Premium Essay

When Rain Clouds Gather Symbolism

...What are the favorite symbols in your life? Two of the main characters in this book are Bobby and Nia. Together they have a baby named Feather. These are the symbols of their lives. The first symbol I remember is on Bobby's birthday. Nia brought him a red balloon and it symbolizes that she is pregnant. Bobby didn't know it at the time but she did. The red of the balloon could also symbolize the pain and the trouble that these two teenagers are going to run in to. Next, we see that after Bobby left feather to go play basketball with K-boy & JL, he stopped and realized what he was doing. He turned around and went back to take care of his baby but when he set the ball down it rolls away like his childhood rolling away. As Nia and Bobby go to the first prenatal doctor visit, Nia imagines she's on a field trip. This means she is getting ready to have a baby and they will be parents and they don't know whether to keep the baby or put it up for adoption. So her pretending to be on a field trip is symbolizing her loss of childhood....

Words: 429 - Pages: 2

Premium Essay

Medieval Iconography Analysis

...study of art, signs and symbols of a particular group in order to understand the underlying meaning. Iconography was used to recover and express the meaning of the symbolic representation portrayed in an art piece rather than just grasping the literal meaning. It is important to Medieval art because most of the time, the actual meaning of the art pieces is not obvious to the naked eye. As a result one must use iconography to do a detailed analysis of the subjects, emotions, scenes and even colors used in order to understand the art better. Additionally, iconography is important because it can be used to analyze art that is grouped together even when some of the pieces in the group are complex, if they belong to the same era and/or...

Words: 459 - Pages: 2

Premium Essay

A Man for All Seasons

...son relationship. “In a neighbour’s house of a Sunday afternoon Mark might stand nearer to him than to anyone else; but he never got onto his lap like the other kids got onto their fathers laps.” This formal relationship definitely reflected on Mark’s garden because towards the ending it didn’t even grow because he didn’t have the right support that he should’ve got from the beginning. The formal respect that they had to one another did turn to mutual right after Mark’s accident with the horses. After that horrible accident Joseph started to express his feelings out to his son mutually. Joseph made sure his son had extra care and that no harm was done to him, “Joseph would be the one who’d quietly put the extra leaves in the dining-room table so they could lay him on it…it would be Joseph’s hand that held the chloroform cone without a tremor.” Joseph did look helplessly out of place, but he’d do anything for his son. Something that significantly changed was the fact that father son relationship that was mentioned beforehand in the beginning of the story drastically changed at the end. The son who never...

Words: 587 - Pages: 3

Free Essay

Codes

... simply select the alt code category you need from the table below. If you need help using alt codes find and note down the alt code you need then visit our instructions for using alt codes page. List of Alt Codes for entering Mathematical Symbols ALT Codes for Mathematical Symbols | Alt Code | Symbol | Description | Alt 48 - 57 | 0 - 9 | zero to nine | Alt Codes for Basic Operators | Alt Code | Symbol | Description | Alt 43 | + | Plus Sign | Alt 45 | - | Minus Sign | Alt 0215 | × | Multiplication Sign | Alt 0247 | ÷ | Obelus / Division ign | Alt Codes for Pers | Alt Code | Symbol | Description | Alt 37 | % | Percentage Sign | Alt 0137 | ‰ | Per mille (per thousand) | Alt Codes for Bracketing | Alt Code | Symbol | Description | Alt 40 | ( | Open Bracket | Alt 41 | ) | Close Bracked | Alt Codes for Degree of Accuracy | Alt Code | Symbol | Description | Alt 241 | ± | Plus or Minus | Alt Codes for Fractions | Alt Code | Symbol | Description | Alt 47 | / | Fraction seperator | Alt 0188 | ¼ | Quarter | Alt 0189 | ½ | Half | Alt 0190 | ¾ | Three quarters | Alt 46 | . | Decimal Point | Alt Codes for Equality | Alt Code | Symbol | Description | Alt 240 | ≡ | Exactly Identical | Alt 61 | = | Equals | Alt 247 | ≈ | Approximately equal | Alt Codes for Inequality | Alt Code | Symbol | Description | Alt 60 | < | Less Than | Alt...

Words: 513 - Pages: 3