Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
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  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
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  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

r"
"
gm

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)(?P<key>\w+) = (?P<val>[^\\]+)`) var str = `{"global_quality": "[general]\ version = 4\ name = Benchy Jonas\ definition = fdmprinter\ \ [metadata]\ setting_version = 6\ type = quality_changes\ quality_type = normal\ \ [values]\ acceleration_enabled = True\ adhesion_type = skirt\ bridge_settings_enabled = True\ jerk_enabled = False\ layer_height = 0.2\ layer_height_0 = 0.2\ magic_spiralize = False\ material_bed_temperature = 50\ material_bed_temperature_layer_0 = 50\ retraction_combing = infill\ speed_slowdown_layers = 1\ support_enable = True\ support_type = buildplate\ travel_retract_before_outer_wall = True\ \ ", "extruder_quality": ["[general]\ version = 4\ name = Benchy Jonas\ definition = fdmprinter\ \ [metadata]\ setting_version = 6\ type = quality_changes\ quality_type = normal\ position = 0\ \ [values]\ acceleration_infill = 1000\ acceleration_print = 500\ acceleration_roofing = 750\ acceleration_topbottom = 1000\ acceleration_travel = 1500\ acceleration_wall_0 = 500\ acceleration_wall_x = 750\ alternate_extra_perimeter = False\ bottom_layers = =999999 if infill_sparse_density == 100 else math.ceil(round(bottom_thickness / resolveOrValue('layer_height'), 4))\ bottom_skin_preshrink = 1.4\ bottom_thickness = 1.2\ bridge_fan_speed = 75\ bridge_fan_speed_2 = 25\ bridge_fan_speed_3 = 33\ brim_line_count = 2\ brim_outside_only = False\ coasting_enable = False\ coasting_speed = 100\ coasting_volume = 0.02\ cool_fan_full_layer = 5\ cool_fan_speed = 75\ cool_fan_speed_max = =cool_fan_speed\ cool_min_layer_time = 5\ cool_min_layer_time_fan_speed_max = 20\ cool_min_speed = 20\ default_material_print_temperature = 230\ fill_outline_gaps = False\ gradual_infill_step_height = 2\ gradual_infill_steps = 0\ gradual_support_infill_step_height = 3\ gradual_support_infill_steps = 1\ infill_before_walls = False\ infill_enable_travel_optimization = True\ infill_line_distance = =0 if infill_sparse_density == 0 else (infill_line_width * 100) / infill_sparse_density * (2 if infill_pattern == 'grid' else (3 if infill_pattern == 'triangles' or infill_pattern == 'trihexagon' or infill_pattern == 'cubic' or infill_pattern == 'cubicsubdiv' else (2 if infill_pattern == 'tetrahedral' or infill_pattern == 'quarter_cubic' else (1 if infill_pattern == 'cross' or infill_pattern == 'cross_3d' else 1))))\ infill_line_width = 0.5\ infill_overlap = 5\ infill_pattern = gyroid\ infill_sparse_density = 7\ infill_support_angle = 75\ infill_support_enabled = False\ ironing_flow = 8\ ironing_inset = 0.25\ ironing_line_spacing = 0.2\ jerk_infill = 20\ jerk_layer_0 = 7\ jerk_print = 7\ jerk_roofing = 10\ jerk_support_infill = 20\ jerk_support_interface = 20\ jerk_topbottom = 20\ jerk_travel = 20\ jerk_travel_layer_0 = 7\ jerk_wall_0 = 8\ jerk_wall_x = 15\ line_width = =machine_nozzle_size\ material_diameter = 1.75\ material_final_print_temperature = =max(-273.15, material_print_temperature - 15)\ material_flow = 99\ material_initial_print_temperature = =max(-273.15, material_print_temperature - 10)\ material_print_temperature = 230\ material_print_temperature_layer_0 = 230\ min_infill_area = 10\ optimize_wall_printing_order = True\ retract_at_layer_change = False\ retraction_amount = 0.8\ retraction_count_max = 100\ retraction_extra_prime_amount = 0\ retraction_extrusion_window = =retraction_amount\ retraction_hop = 0.2\ retraction_hop_enabled = True\ retraction_hop_only_when_collides = True\ retraction_min_travel = 1\ retraction_prime_speed = 25\ retraction_retract_speed = 25\ retraction_speed = 70\ roofing_layer_count = 0\ roofing_pattern = concentric\ skin_no_small_gaps_heuristic = False\ skin_overlap = =5 if top_bottom_pattern != 'concentric' else 0\ skirt_brim_line_width = =line_width\ skirt_brim_minimal_length = 175\ skirt_brim_speed = 20\ skirt_gap = 5\ skirt_line_count = 3\ speed_equalize_flow_enabled = False\ speed_equalize_flow_max = 60\ speed_infill = 50\ speed_ironing = 60\ speed_layer_0 = 20\ speed_print = 50\ speed_roofing = 50\ speed_support = 50\ speed_support_infill = 60\ speed_support_interface = 50\ speed_topbottom = 50\ speed_travel = 175\ speed_wall = =speed_print / 2\ speed_wall_0 = 25\ speed_wall_x = =speed_wall * 2\ support_angle = 67\ support_infill_rate = 10\ support_infill_sparse_thickness = =resolveOrValue('layer_height')\ support_interface_density = 50\ support_interface_enable = True\ support_interface_pattern = lines\ support_interface_skip_height = 0.2\ support_line_width = 0.5\\nsupport_minimal_diameter = 2\ support_offset = 0.4\ support_pattern = zigzag\ support_roof_height = 1\ support_top_distance = =extruderValue(support_roof_extruder_nr if support_roof_enable else support_infill_extruder_nr, 'support_z_distance')\ support_tower_diameter = 5\ support_tower_roof_angle = 30\ support_use_towers = True\ support_wall_count = 1\ support_xy_distance = 0.6\ support_xy_distance_overhang = 0.5\ support_xy_overrides_z = xy_overrides_z\ support_z_distance = 0.2\ top_bottom_pattern = lines\ top_bottom_pattern_0 = lines\ top_bottom_thickness = 1.6\ top_layers = =0 if infill_sparse_density == 100 else math.ceil(round(top_thickness / resolveOrValue('layer_height'), 4))\ top_skin_preshrink = 1.2\ top_thickness = 1.6\\ntravel_avoid_other_parts = False\ travel_avoid_supports = True\ travel_compensate_overlapping_walls_0_enabled = =travel_compensate_overlapping_walls_enabled\ travel_compensate_overlapping_walls_enabled = False\ travel_compensate_overlapping_walls_x_enabled = =travel_compensate_overlapping_walls_enabled\ wall_0_wipe_dist = =machine_nozzle_size / 2\ wall_line_count = 3\ wall_line_width_0 = 0.4\ wall_line_width_x = =wall_line_width\ wall_thickness = 2\ xy_offset_layer_0 = -0.05\ z_seam_corner = z_seam_corner_inner\ z_seam_relative = True\ z_seam_type = back\ z_seam_x = -250\ z_seam_y = -30\ \ "]} ` for i, match := range re.FindAllString(str, -1) { fmt.Println(match, "found at index", i) } }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Golang, please visit: https://golang.org/pkg/regexp/