A text string pattern matching mechanism. Usually applied to individual lines of text, such as from a simple text file, where the regular expression (sometimes abbreviated as RE) pattern can be used to precisely specify which lines ought to match and which shouldn't. The more complicated REs may look very confusing to people who don't know them, as they look more like a random string of letters and other characters without any obvious meaning.
Commonly they're enclosed between slashes (/like this/), because that's how they were used in many ancient Unix tools. They can also be used for text substitution, for example with the s/ construct. A common operator specifying that a RE will follow is the tilde (~).
The Perl language makes heavy use of regular expressions, and the grep tool also searches by REs. SED and AWK are some older tools also using REs.
REs come in two forms: Basic REs and Extended REs, varying slightly in syntax and possible contructs. Perl extens the Extended REs even further and has defined the standard "Perl Compatible REs" (PCRE).
Commonly they're enclosed between slashes (/like this/), because that's how they were used in many ancient Unix tools. They can also be used for text substitution, for example with the s/ construct. A common operator specifying that a RE will follow is the tilde (~).
The Perl language makes heavy use of regular expressions, and the grep tool also searches by REs. SED and AWK are some older tools also using REs.
REs come in two forms: Basic REs and Extended REs, varying slightly in syntax and possible contructs. Perl extens the Extended REs even further and has defined the standard "Perl Compatible REs" (PCRE).
"some example string" =~ /^s*.*e+.*(?:x.* )?.*?g$/
result: 1 (because the regular expression between the // matches the string)
result: 1 (because the regular expression between the // matches the string)
by DJMoses May 27, 2009
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Of, or relating to, the outward display of expression or emotion. Specifically when it proves Mike wrong.
by BHoudini2 March 25, 2020
Get the Expressionable mug.by Scary turtle May 22, 2020
Get the Expressionate mug.Used when It is blatantly obvious that someone is being racist. Definitely to be used when you are a female minority referring to a white male.
Sarah: “I mean I don’t know, Chung Lee’s eyes were as if he was looking at the sun while he was talking to me.”
Evan: “Wow Sarah, your racial expression is real strong. Maybe have some tea.”
Evan: “Wow Sarah, your racial expression is real strong. Maybe have some tea.”
by RacialChow February 11, 2019
Get the Racial Expression mug.A nano-expression is a very brief, involuntary facial expression shown on the face of humans according to emotions experienced. They usually occur in high-stakes situations, where people have something to lose or gain. Unlike regular facial expressions, it is difficult to fake nanoexpressions.
Nano-expressions express seven universal emotions as microexpressions: disgust, anger, fear, sadness, happiness, surprise, and contempt. They can occur as fast as 1/05 to 1/14 of a second.
by 200lies.com December 18, 2010
Get the Nano-expression mug.An internet lingo created to battle the the overuse of the term lol by using different abbreviations to more accurately describe the user's expressions.
1. NL=Not Laughing. Used when a friend makes an unfunny joke but thought it was hilarious.
2. Ss=Slight Smile. Used when the user has a slight smile on their face, an expression that many people described innacurately with the term "lol".
3. Cg=Cracked Grin. Used when the user is halfway between a slight smile and loling.
4. Lol=Laughing out loud. Only to be used when the user is literally laughing audibly in a text or online chat.
1. NL=Not Laughing. Used when a friend makes an unfunny joke but thought it was hilarious.
2. Ss=Slight Smile. Used when the user has a slight smile on their face, an expression that many people described innacurately with the term "lol".
3. Cg=Cracked Grin. Used when the user is halfway between a slight smile and loling.
4. Lol=Laughing out loud. Only to be used when the user is literally laughing audibly in a text or online chat.
1. Guy A: Why did the chicken cross the road? To get to the other side!
Guy B: NL...
2. Guy A: That guy gets more ass than a toilet seat...
Guy B: Ss, that was slightly amusing.
3. Guy A: I smoked a pound of weed one time and pissed all over my friend's pet hamster.
Guy B: Cg, that is pretty damn funny...
4. Guy A: That chick is like a broken traffic light. Green light all the time!
Guy B: Lol, i am literally laughing audibly so that others in the room can hear me, and am not in any way just saying "lol" to show how extremely uninterested I am.
Guy A: I love how you used expressionism as a way to convey your true emotions.
Guy B: NL...
2. Guy A: That guy gets more ass than a toilet seat...
Guy B: Ss, that was slightly amusing.
3. Guy A: I smoked a pound of weed one time and pissed all over my friend's pet hamster.
Guy B: Cg, that is pretty damn funny...
4. Guy A: That chick is like a broken traffic light. Green light all the time!
Guy B: Lol, i am literally laughing audibly so that others in the room can hear me, and am not in any way just saying "lol" to show how extremely uninterested I am.
Guy A: I love how you used expressionism as a way to convey your true emotions.
by grovecityfan July 7, 2008
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