Regular Expressions 101

^start of line

Group 1(\s*(?<!#)\s*PRIMER_PRODUCT_SIZE_RANGE\s*)

\s*a Unicode whitespace character, repeated any number of times

Negative Lookbehind(?<!#)

#the literal # (35₁₀ / 43₈ / 23₁₆)

\s*a Unicode whitespace character, repeated any number of times

PRIMER_PRODUCT_SIZE_RANGEthe literal text PRIMER_PRODUCT_SIZE_RANGE (case sensitive)

\s*a Unicode whitespace character, repeated any number of times

=the literal = (61₁₀ / 75₈ / 3D₁₆)

.*any Unicode character (except for line terminators), repeated any number of times

$end of line

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

^(\s*(?<!#)\s*PRIMER_PRODUCT_SIZE_RANGE\s*)=.*$

# PRIMER_PRODUCT_SIZE_RANGE=xxx-yyy
PRIMER_PRODUCT_SIZE_RANGE=100-300
PRIMER_NUM_RETURN=3
PRIMER_MAX_END_STABILITY=9.0

PRIMER_MAX_HAIRPIN_TH=24.0

\1=500-300